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NORTH  CAROLINA  GEOLOGICAL  AND  ECONOMIC  SURVEY 


JOSEPH  HYDE  PRATT,  Director  and  State  Geologist 


BULLETIN  No.  33 


The  Deep  River  Coal  Field 
of  North  Carolina 


BY 

MARIUS  R.  CAMPBELL  and  KENT  W.  KIMBALL 


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Prepared  by 

United  States  Geological  Survey 

In  Cooperation  with  the 

North  Carolina  Geological  and  Economic  Survey 


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GEOLOGICAL  BOARD 


Govern  ok  Cameron  Morrison,  ex  officio  chairman Raleigh 

Frank  R.  Hewitt Asheville 

C.  C.  Smoot,  III  North  Wilkesboro 

John  H.  Small Washington 

S.  Westray  Battle Asheville 


Joseph  Hyde  Pratt,  Director  and  State  Geologist Chapel  Hill 


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LETTER  OF  TRANSMITTAL 


Chapel  Hill,  1ST.  C.,  June  1,  1923. 
To  //is  Excellency,  Cameron  Morrison, 

Governor  of  North  Carolina. 

Sir  : — There  has  just  been  completed  a report  on  “The  Deep  River 
Coal  Field  of  North  Carolina,”  which  has  been  prepared  by  the  State 
Survey  in  cooperation  with  the  United  States  Geological  Survey.  The 
investigation  of  this  coal  field  has  aroused  a great  deal  of  interest 
throughout  the  State  in  regard  to  the  occurrence  of  a commercial 
quantity  of  coal  in  North  Carolina.  There  is  a very  large  demand  for 
information  regarding  this  occurrence,  and  I would  submit  the  report 
for  publication  as  Bulletin  No.  33  of  the  series  of  publications  of  the 
North  Carolina  Geological  and  Economic  Survey. 

Yours  respectfully, 

Joseph  Hyde  Pratt,  Director, 

North  Carolina  Geological  and  Economic  Survey. 


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TABLE  OF  CONTENTS 


Page 

Preface  7 

Introduction  ! 11 

General  statement  11 

History  of  discovery  and  development 12 

Present  investigation  16 

Geography  of  the  field 17 

Geologic  formations  18 

General  statement  IS 

Pekin  formation  21 

Cumnock  formation  25 

General  statement  25 

In  the  Carthage  trough  28 

As  offset  by  the  Deep  River  fault 35 

In  the  Corinth  trough  41 

Sanford  formation  43 

Igneous  dikes  45 

Geologic  structure  49 

General  statement  49 

Carthage  trough  50 

General  description  50 

Minor  structures 51 

Colon  cross-structure  54 

Corinth  trough  55 

Jonesboro  fault 55 

History  of  the  development  of  geologic  structure 60 

General  statement  60 

Deformation  accompanying  sedimentation  — 60 

Torsional  stresses  resulting  in  cross-structure 61 

Normal  faulting  in  a longitudinal  direction 62 

The  coal  64 

Thickness  of  the  coal  beds 64 

Extent  of  workable  coal  and  available  tonnage 76 

Character  of  the  coal  SO 

Tests  by  the  Bureau  of  Mines - S6 

Possibilities  of  Petroleum  01 


LIST  OF  PLATES 


Plate  Page 


1 Map  of  the  Deep  River  Coal  Field In  pocket 

2 A.  Deep  River  from  the  Horseshoe  Bridge 18 

B.  Outcrop  of  the  Cumnock  coal  bed  near  Gulf 18 

3 The  Cumnock  coal  mine 28 

4 A.  Boulders  of  schist  in  the  Sanford  formation 44 

B.  Boulder  of  granite  in  the  Sanford  formation 44 

5 A.  Minute  dikes  euting  red  saudstoue 48 

B.  Sandstone  tilted  by  a dike 48 

6 A.  Hydroelectric  plant  at  Carbonton 54 

B.  Dike  cutting  shale  irregularly 54 

7 Jonesboro  fault  in  railroad  cut 60 

Figure 

1 Section  of  Cumnock  formation,  as  exposed  in  the  Cumnock  shaft 

and  in  boreholes  on  the  Cumnock  property 27 

2 Cross  sections  showing  the  probable  effect  of  the  Carbonton  fault 

on  the  outcrop  of  the  Cumnock  formation  between  Carbonton  and 
Horseshoe  Bend  of  Deep  River 32 

3 Diagram  showing  various  forms  that  normal  faults  may  assume 53 

4 Diagram  showing  the  character  of  the  Jonesboro  fault 59 

5 Sections  of  coal  beds  66 

6 Graph  illustrating  comparative  heating  values  of  competing  coals 86 

7 Diagram  showing  form  of  oil  pools  in  an  anticline 93 


- ■ 


: ; 


* 


PREFACE 


For  about  one  hundred  and  fifty  years  coal  has  been  known  to  occur 
in  North  Carolina,  and  for  many  years  there  has  been  more  or  less 
interest  aroused  amongst  our  people  as  to  the  possibility  of  developing 
commercial  fields  of  coal.  Considerable  prospecting  and  some  mining 
has  been  done  during  this  period,  but  most  of  the  work  was  a failure 
due  to  several  causes,  chief  of  which  perhaps  was  lack  of  capital  and 
having  men  unfamiliar  with  coal  mining  in  charge  of  operations.  As 
a result  the  public  began  to  consider  that  either  the  coal  was  so  poor 
or  the  mining  conditions  so  bad  that  it  was  doubtful  if  coal  mining 
could  ever  be  made  to  pay.  This  was  probably  a natural  sequence 
considering  what  was  known  of  the  occurrence  of  some  of  the  coal 
which  was  in  very  thin  seams  and  obviously  could  not  be  worked 
profitably.  Also  considerable  of  the  coal  that  was  first  used  was 
weathered  and  did  not  have  the  heating  properties  expected  of  it. 
The  present  investigation  was  undertaken  with  the  idea  that  the  coal 
of  the  Deep  River  Field  is  much  more  valuable  than  has  been  generally 
believed  and  that  it  should  become  a source  of  fuel,  not  only  for  mills 
and  railroads  of  Eastern  North  Carolina,  but  for  a domestic  use  in  the 
form  of  coke. 

There  are  two  areas  in  the  State  in  which  coal  occurs : one  known  as 
the  Deep  River  Coal  Field  covering  portions  of  Chatham,  Lee  and 
Moore  counties,  and  which  is  described  in  detail  in  this  report ; and  the 
other,  the  Dan  River  Coal  Field  covering  portions  of  Stokes  and  Rock- 
ingham counties.  The  coal  beds  of  both  these  fields  occur  in  sandstones 
and  shales  of  Triassic  age,  which  outcrop  in  comparatively  narrow 
belts. 

The  Dan  River  Field  has  been  described  in  detail  by  Mr.  R.  W.  Stone, 
Geologist  of  the  United  States  Geological  Survey,  in  Economic  Paper 
34,  1914,  pages  115-149,  of  the  State  Survey’s  publications;  and  the 
conclusion  reached  in  regard  to  this  coal  field  was  that  “after  a thorough 
and  careful  examination  of  the  Triassic  beds  in  the  Dan  River  Field 
the  conclusion  is  reached  that  there  is  no  reason  to  expect  to  find 
commercially  valuable  coal  beds  in  this  district.”  This  report  sub- 
stantiated the  information  that  the  Survey  had  regarding  this  field, 
and  since  this  report  came  out  there  has  been  no  further  prospecting 
or  consideration  given  to  this  field  from  a commercial  standpoint. 

The  Deep  River  Coal  Field  has  been  investigated  from  time  to  time 
over  a period  of  nearly  one  hundred  years,  but  only  one  of  these 
investigations  was  more  than  a superficial  examination.  This  was  the 


PREFACE 


report  of  Dr.  H.  M.  Chance,  made  in  1884-85  for  the  North  Carolina 
Department  of  Agriculture.  Dr.  Chance’s  conclusions,  which  were  not 
particularly  favorable  and  which  are  discussed  in  this  report,  were 
that  in  the  area  described  “the  prospects  are  sufficiently  encouraging 
to  warrant  a thorough  exploration  of  each  individual  tract  by  the 
landowners;  that  in  the  area  between  Farmville  and  Gulf  two  beds  of 
coal  exist  that  may  be  considered  workable.” 

In  discussing  the  subject  the  authors  give  a very  interesting  history 
of  the  discovery  and  development  of  coal  in  this  field.  It  seems  evident 
that  the  coal  was  discovered  at  Gulf  some  time  prior  to  1775,  and  from 
that  time  to  the  present  there  has  been  considerable  uncertainty  as  to 
the  quantity  and  quality  of  the  coal  in  the  area. 

The  geography  of  the  field  shows  it  to  extend  from  a short  distance 
northeast  of  Cape  Fear  River  in  a southwesterly  direction  to  Carthage 
and  in  the  other  direction  from  Sanford  on  the  southwest  to  a few 
miles  beyond  Gulf  on  the  northwest,  embracing  portions  of  Chatham, 
Lee  and  Moore  counties.  It  is  known  and  designated  as  the  Deep 
River  Coal  Field  because  almost  all  the  prospecting  and  developing 
has  been  on  or  near  that  stream  from  near  Glendon  to  the  point  where 
Deep  and  Haw  rivers  unite  to  form  the  Cape  Fear.  The  area  in  which 
the  presence  of  coal  has  been  demonstrated  is  only  a small  part  of  the 
area  outlined  above. 

The  geologic  formations  and  structure  cover  a considerable  portion 
of  the  report  and  are  discussed  in  great  detail.  The  coal  beds  are 
associated  with  sandstones  and  shales  which  are  of  Triassic  age  and 
belong  to  the  Newark  group.  This  Newark  group  of  rocks  includes 
the  red  sandstones  of  the  Connecticut  Yalley  in  Connecticut  and 
Massachusetts,  and  the  red  sandstone  and  shale  of  Virginia.  This 
Newark  group  in  the  Deep  River  Field  consists  of  three  generally 
recognized  parts : a lower  formation  to  which  the  name  Pekin  has  been 
given,  composed  largely  of  red  and  brown  sandstone;  a middle  forma- 
tion of  light  colored  or  drab  shale,  sandstone  and  coal  beds,  to  which 
has  been  given  the  name  Cumnock ; and  an  upper  formation  called 
the  Sanford,  consisting  mainly  of  red  conglomerate  of  great  though 
unknown  thickness.  This  portion  of  the  report  also  describes  the 
character  and  location  of  the  dikes  cutting  through  the  formations,  and 
faults  that  were  noted;  and  shows  cross-sections  of  the  formation  at 
various  places  throughout  the  area.  A geologic  map  of  the  area  also 
accompanies  the  report. 

In  describing  the  coal,  attention  is  called  to  the  occurrence  of  two 
oenches  known  as  the  upper  and  lower.  Formerly  in  speaking  of  the 
thickness  of  the  coal  beds  both  benches  were  included  in  the  width 


PREFACE 


9 


given  as  seven  feet  six  inches,  and  it  is  believed  that  this  entire 
thickness  was  originally  mined.  It  is  only  the  upper  bench,  where  the 
coal  varies  in  thickness  from  three  feet  to  nearly  four  feet,  that  is 
considered  at  the  present  time  as  commercial  coal,  although  it  is 
believed  that  under  certain  conditions  this  lower  bench  might  be  mined 
and  cleaned  profitably.  The  extent  of  the  workable  coal  and  available 
tonnage  is  estimated  by  the  geologists  as  approximately  sixty-eight 
million  tons  of  recoverable  coal  in  the  district  west  of  the  Deep  River 
fault;  and  that  mining  can  be  carried  on  profitably  to  a depth  of  two 
thousand  feet.  The  area  in  which  this  tonnage  is  included  is  about 
twenty-five  square  miles,  and  it  is  considered  reasonable  to  assume  that 
the  coal  bed  throughout  this  area  averages  at  least  three  feet  in  thick- 
ness of  recoverable  coal.  The  character  and  quality  of  the  coal  have 
been  very  carefully  studied  and  physical  and  chemical  analyses  are 
given  of  coal  taken  from  various  sections  of  the  area.  One  interesting 
feature  of  the  chemical  composition  of  the  coal  is  that  it  contains 
approximately  two  per  cent  of  nitrogen,  which  could  be  obtained  in 
the  form  of  ammonium  sulphate  as  a by-product  in  coking  the  coal, 
which  would  give  approximately  twenty-three  pounds  per  ton  of  coal. 
The  coking  test  showed  that  the  coal  would  make  a coke  of  very  good 
quality  in  so  far  as  could  be  determined  by  a laboratory  test  and  is 
fairly  equal  to  either  Freeport  or  Pittsburgh  cokes.  It  is  believed  that 
one  use  of  the  Deep  River  coal  that  should  be  given  careful  considera- 
tion is  to  coke  it,  using  the  coke  obtained  as  a domestic  fuel,  and  the 
yield  of  gas  for  generating  electric  power  for  transmission. 

The  ammonium  sulphate,  obtained  as  a by-product,  will  be  of  large 
value  for  agricultural  purposes.  There  would  also  be  obtained  as 
another  by-product  approximately  twenty-two  gallons  of  tar  (dehy- 
drated) per  ton  of  coal.  The  by-product  yield  in  coking  this  coal 
compares  very  favorably  with  yields  from  Freeport  coal. 

The  report  also  discusses  briefly  the  possibilities  of  oil  in  the  area, 
and  the  conclusions  of  the  geologists  are  that  from  a geological  point 
of  view  all  the  evidence  collected  in  the  field  bearing  on  this  question 
is  of  a negative  character. 

The  present  report  has  been  prepared  through  the  cooperation  of 
the  United  States  Geological  Survey  and  the  ISTorth  Carolina  Geological 
and  Economic  Survey.  Geologists  were  detailed  from  the  Federal 
Survey  staff  to  make  the  investigation.  The  United  States  Bureau 
of  Mines  also  cooperated  in  the  investigation  by  sampling  the  coal  and 
making  chemical  and  physical  analyses  and  washing  and  coking  tests 
of  same. 


10 


PREFACE 


The  Director  of  the  Survey,  who  made  several  trips  into  the  field 
during  the  investigation,  wishes  to  extend  the  thanks  of  the  Survey 
and  of  the  geologists  making  the  investigation  to  the  citizens  of  the 


community  for  their  kindness  and  courtesy  in  assisting  in  securing 
data  on  the  mineral  resources  of  the  area.  Others  who  were  particularly 
interested  in  the  coal  itself  were  most  liberal  in  giving  their  services 
and  means  at  all  times,  and  the  Survey  desires  at  this  time  to  express 
its  special  thanks  to  Mr.  Charles  Reeves  of  Sanford,  Mr.  William  Hill 
of  Cumnock,  Mr.  Bion  Butler  of  Southern  Pines,  Mr.  J.  S.  Cox  of  the 
Norfolk  Southern  Railway,  General  E.  F.  Glenn  of  Glendon,  Dr.  M.  E. 
Street  of  Carthage,  and  Mr.  Mclver,  for  these  services. 

While  the  history  of  coal  mining  operations  in  this  Deep  River  Field 
has  been  one  of  many  failures  due  to  lack  of  adequate  capital  to  develop 
a mine  under  the  prevailing  mining  conditions,  to  lack  of  experience 
in  coal  mining  of  those  in  charge  of  the  work,  and  to  lack  of  adequate 
transportation  facilities,  today,  on  account  of  changed  conditions  of 
marketing  and  transportation  facilities  and  the  thousands  of  homes 
calling  for  domestic  fuel  supply,  there  seems  to  he  no  reason  why  the 
mining  operations  should  not  be  reasonably  successful.  This  of  course 
is  predestined  on  there  being  an  adequate  supply  of  coal  that  can 
be  obtained  at  moderate  cost,  the  probability  of  which  is  discussed 
in  this  report. 


Director, 


North  Carolina  Geological  and  Economic  Survey. 


The  Deep  River  Coal  Field 
of  North  Carolina 


by 

MARIUS  R.  CAMPBELL  and  KENT  K.  KIMBALL 


INTRODUCTION 

General  Statement 

The  Deep  River  coal  field  of  ISTorth  Carolina  (see  Key  map  on  PI. 
1 in  pocket),  although  it  has  been  known  for  about  150  years,  has 
had  an  unfortunate  history  of  failure  after  failure  in  attempts  to  mine 
and  market  the  coal,  until  the  general  public  has  either  forgotten  that 
such  a coal  field  exists,  or  is  strongly  imbued  with  the  idea  that  the 
coal  is  so  poor  and  the  mining  conditions  are  so  bad,  that  it  is  doubtful 
if  it  ever  could  be  made  to  pay.  The  present  report  contains  the 
results  of  a recent  examination  by  geologists  of  the  United  States 
Geological  Survey  cooperating  with  the  ISTorth  Carolina  Geological  and 
Economic  Survey,  which  shows  that  the  coal  is  of  excellent  quality; 
that  the  mining  conditions  are  fairly  good  for  a rather  steeply  dipping 
coal  bed;  and  that  the  general  conditions  in  the  surrounding  region 
are  favorable  for  the  development,  on  a larger  scale  than  has  ever 
been  attempted,  of  that  part  of  the  margin  of  the  trough  extending 
from  Cumnock  (PL  1,  in  pocket)  south  westward  at  least  to  Carbonton, 
and  possibly  from  Cumnock  for  a few  miles  southeastward  toward 
Colon. 

The  coal  beds  of  the  Deep  River  Field  occur  in  sandstone  and  shale 
of  Triassic  age,  which  crop  out  in  a comparatively  narrow  belt  from 
Oxford  near  the  northern  border  of  the  State  to  the  South  Carolina 
line,  twelve  or  fifteen  miles  west  of  Pee  Dee  River.  Coal  has  been 
reported  at  many  places  in  this  belt,  but  the  only  known  coal  of  com- 
mercial importance  is  found  on  Deep  River,  west  and  northwest  of 
Sanford. 

It  was  found  necessary,  before  attempting  a study  of  geologic  con- 
ditions in  the  Deep  River  Field,  to  make  a base  map  upon  which  the 
geologic  data  could  be  plotted,  as  no  map  of  this  region,  worthy  of 
the  name,  could  be  found.  The  map,  shown  in  Plate  1,  is  the  result 
of  a survey  carried  on  by  the  junior  author  assisted  by  William  J.  Cox 
and  Lynn  J.  Adcock,  and  much  of  the  success  of  the  report  is  due  to 
the  indefatigable  work  of  these  men  in  covering  the  ground  in  the 
appointed  time.  The  survey  was  made  with  plane-table  and  telescopic 
alidade  and  distances  were  determined  by  stadia  measurements.  When 
the  major  part  of  the  map  had  been  completed  it  was  found  that  the 


12 


THE  DEEP  RIVER  COAL  FIELD 


dikes,  which  are  present  in  great  numbers,  are  magnetic  and  have  a 
decided  influence  on  the  magnetic  needle  of  the  plane-table.  As  courses 
were  determined  by  this  needle,  any  local  attraction  produced  by  a 
dike  would  tend  to  cause  an  error  in  the  direction  of  the  line  being 
surveyed.  Owing  to  this  source  of  local  attraction  many  errors  will 
be  found  in  the  directions  of  the  roads,  and  the  geographic  relations  of 
features  shown  on  the  map  may  be  quite  different  in  detail  from  the 
relations  of  the  same  features  on  the  ground ; but,  as  the  local  variation 
due  to  one  dike  may  be  in  an  opposite  direction  from  that  due  to 
another  dike,  the  effect  of  one  tends  to  neutralize  the  effect  of  the 
other  and  for  that  reason  the  map,  taken  as  a whole,  is  approximately 
correct.  The  public  is,  however,  cautioned  against  depending,  in  im- 
portant matters,  solely  upon  this  map  for  distances  and  directions  of 
surveyed  lines  and  acreage  inclosed  by  such  lines. 

In  carrying  on  both  the  topographic  and  the  geologic  work  in  this 
field,  the  writers  found  the  citizens,  as  a rule,  willing  and  anxious  to 
help  in  securing  data  on  the  mineral  resources  of  the  country;  and  as 
it  is  impossible  to  enumerate  individuals  who  furnished  information 
of  this  sort,  the  writers  wish  to  extend  their  thanks  to  all  for  their 
kindness  and  courtesy.  Those  who  are  most  deeply  interested  in  the 
coal  itself  contributed  in  many  ways  to  the  success  of  the  work;  chief 
among  those  who  gave  their  services  and  means  at  all  times  are  Mr. 
Charles  Reeves,  who  assisted  very  materially  by  furnishing  information 
regarding  coal  prospects,  maps,  and  the  result  of  drilling  operations 
of  the  Carolina  Coal  Company;  Mr.  William  Hill,  then  General 
Manager  of  the  Cumnock  Coal  Company,  who  assisted  the  writers  in 
gathering  information  concerning  the  Cumnock  mine,  the  prospecting 
work  that  had  been  done  by  the  Cumnock  Coal  Company  and  the  logs 
of  deep  wells  which  the  company  had  drilled  on  its  property;  Mr. 
Bion  Butler  of  Southern  Pines,  who  furnished  geologic  data  which 
has  been  of  great  value  in  solving  some  of  the  difficult  problems 
encountered  in  the  field,  and  without  which  the  writers  would  have 
found  it  impossible  to  have  completed  their  work  in  the  time  alloted 
for  that  purpose;  and  Mr.  J.  S.  Cox,  local  superintendent  of  the  Horfolk 
Southern  Railroad  for  a motor  car  trip  over  this  line  from  Hemp  to 
Raleigh.  General  E.  F.  Glenn,  Doctor  M.  E.  Street  and  Mr.  Mclver 
were  also  helpful  in  furnishing  information  regarding  general  conditions 
and  in  assisting  the  writers  in  getting  about  the  field. 

History  of  Discovery  and  Development 

The  history  of  the  discovery  and  development  of  coal  in  this  field 
has  never  been  recorded  in  print,  and  consequently  much  of  it  has 
been  lost,  or  if  preserved,  it  exists  only  in  tradition. 


THE  DEEP  RIVER  COAL  FIELD 


13 


The  first  published  account  of  coal  that  the  writers  have  discovered 
is  contained  in  a letter  written  by  Professor  Olmsted1  from  Chapel 
Hill  in  1820.  In  this  letter  he  says : 

An  extensive  secondary  formation  lias  lately  been  discovered  near  us.  On 
the  road  between  this  place  and  Raleigh,  traveling  eastward,  we  come  to  it 
four  miles  from  the  college;  but  at  another  point  it  has  been  discovered 
within  two  miles  of  us.  It  is  a sandstone  formation  . . . 

It  was  natural  to  look  for  coal  here  and  I have  for  some  time  directed  the 
attention  of  my  pupils,  and  of  stonecutters  to  this  object.  Two  or  three  days 
since  one  of  the  latter  brought  me  a handful  of  coal,  found  in  this  range,  on 
Deep  River,  in  Chatham  County,  about  20  miles  south  of  this  place.  The 
coal  is  highly  bituminous,  and  burns  with  a very  clear  and  bright  flame.  It 
is  reported  that  a sufficient  quantity  has  already  been  found  to  afford  an 
ample  supply  for  the  blacksmiths  in  the  neighborhood. 

From  the  quotation  just  given,  it  would  seem  that  the  Deep  River 
coal  was  discovered  only  a few  years  before  1820.  It  is,  however, 
probable  that  it  had  been  known  locally  for  many  years,  but  had  not 
been  brought  to  the  attention  of  the  State  Geologist.  This  view  of 
the  case  is  substantiated  by  Professor  Olmsted’s  2 3 statement  in  his  report 
of  1824,  which  is  as  follows : 

In  addition  to  the  foregoing  presumptions  that  coal  might  be  found  in  the 
district  of  country  under  consideration,  we  have  it  in  our  power  to  say  that 
coal  has  actually  been  discovered  in  this  region,  and  that  a bed  of  consider- 
able extent  has  been  opened  not  far  from  the  Gulf3  on  Deep  River. 

It  is  about  50  years  since  this  coal  bed  was  first  discovered.  Mr. 
Wilcox,  an  enterprising  gentleman,  proprietor  of  the  Old  Iron  Works  at  the 
Gulf,  took  some  pains  to  have  it  opened,  and  to  introduce  the  coal  into  use. 

Professor  Emmons4  corroborates  this  statement  in  his  report  of  1852 
in  which  he  says : “It  [the  Horton  mine  at  Gulf]  was  known  in  the 

Revolution,  and  a report  made  to  Congress,  respecting  it,  is  still  extant.” 
The  writers  have  searched  for  this  report,  but  have  not  been  able  to 
find  it. 

It  also  is  probable  that  the  outcrop  of  the  coal  beds  from  Farmville 
to  Carbonton  was  known  and  prospected  in  the  early  part  of  the 
nineteenth  century.  Chance5  says: 

Coal  was  dug  from  open  pits  for  blacksmithing  in  the  Deep  River  coal  field 
early  in  this,  if  not  indeed  in  the  last  century,  but  no  systematic  attempt  was 

101msted,  Prof.  D.,  Red  sandstone  formation  of  North  Carolina,  Am.  Jour.  Sci.,  vol.  2, 
page  175,  1820. 

2See  manuscript,  page  5. 

3The  name  Gulf  was  given  to  the  settlement  at  the  sharp  bend  of  Deep  River,  by  boat- 
men who  found  here  an  unusually  deep  portion  of  the  river  between  shallows  formed  by 
the  dikes  where  they  cross  the  stream. 

‘Emmons,  Ebenezer,  Report  of  Professor  Emmons  in  his  Geological  Survey  of  North 
Carolina,  p.  131,  Raleigh,  1852. 

“Chance,  H.  M.,  Report  on  North  Carolina  coal  fields  to  the  Department  of  Agriculture, 
p.  23,  Raleigh,  1885. 


14 


THE  DEEP  RIVER  COAL  FIELD 


made  to  open  the  field  to  market  until  the  slackwater  improvement  of  the 
Deep  River.  As  these  improvements  were  seriously  damaged  by  floods  sood 
after  the  completion,  the  people  were  discouraged  from  further  attempts  at 
that  time.  The  next  attempts  were  made  upon  the  completion  of  the  rail- 
road from  Fayetteville  to  Egypt  and  the  Gulf.  Some  coal  was  shipped  ovei 
this  road  from  the  shaft  at  Egypt,  but  the  cost  of  transportation  to  Fayette- 
ville and  trans-shipment  and  towing  down  the  Cape  Fear  River  to  Wilming- 
ton ...  on  a river  full  of  shoals,  was  doubtless  too  great  to  leave  any  profit. 
Operations  were  most  actively  pushed  in  the  period  immediately  preceding 
the  [Civil]  war.  During  the  war  coal  was  mined  at  Farmville,  Egypt,  Gulf, 
and  the  Evans’  place,  and  shipped  by  river  to  Fayetteville  and  to  Wilmington, 
where  it  was  used  to  some  extent  by  blockade  runners,  but  the  aggregate 
amount  thus  shipped  must  have  been  quite  small. 

From  tlie  quotations  given  above  and  from  information  gathered 
in  the  field  it  seems  evident  to  the  writers  that  the  coal  of  this  field 
was  discovered  at  the  Gulf  some  time  previous  to  1775  and  that  the 
Horton  coal  mine  was  in  operation  at  that  place  at  least  some  of  the 
time  during  the  Revolution,  but  without  doubt  the  mine  was  operated 
in  a small  way  to  supply  local  needs. 

It  is  also  probable  that  within  the  next  50  years  after  the  Horton 
mine  was  opened  the  outcrop  of  the  coal  bed  had  been  prospected  and 
was  fairly  well  known  from  Farmville  (now  the  Carolina  coal  mine) 
at  least  as  far  as  Gulf.  Peter  Evans,  who  owned  the  plantation  in  the 
great  northward  bend  of  Deep  River,  including  the  village  now  known 
as  Cumnock,  began  mining  coal,  it  is  reported,  on  his  property,  then 
called  Egypt1  in  1830. 

In  1851  the  Egypt  plantation  was  sold  to  L.  J.  Houghton  and  Brooks 
Harris.  Harris  soon  acquired  the  interest  of  Houghton,  and  in  1852 
sank  the  Egypt  shaft,  probably  the  most  important  single  piece  of 
development  work  ever  undertaken  in  this  coal  field.  The  shaft  pierced 
the  principal  or  Cumnock  coal  bed  at  a depth  of  430  feet,  but  was 
continued  to  a total  depth  of  460  feet.  The  property  changed  hands 
frequently,  and  in  1854  passed  into  the  ownership  of  the  Governors 
Creek  Steam  Transportation  and  Mining  Company,  which  operated 
the  mine  until  after  the  Civil  War  when,  by  order  of  the  Convention, 
the  name  was  changed  to  “The  Egypt  Company.” 

The  market  for  this  coal  was  then  largely  to  the  east  and  the  great 
problem  was  to  get  it  to  seacoast  cities  at  a cost  that  would  enable 
it  to  be  sold  at  a profit,  in  competition  with  coals  from  other  fields. 
Two  lines  of  outlet  for  the  coal  were  considered:  (1)  an  all-water 

1The  original  name  of  the  settlement  on  this  plantation  was  LaGrange.  but  this  name 
was  changed  by  Peter  Evans  to  Egypt,  as  the  result  of  a facetious  remark  by  one  of  his 
neighbors.  One  day,  as  the  story  goes,  Evans  met  Peter  Smith,  a Scotchman,  on  the  road 
and  asked  him  where  he  was  going.  Smith  replied  that  he  was  going  to  the  “land  of 
Egypt”  to  get  corn.  Evans  was  so  pleased  with  having  his  plantation  called  “The  land 
of  Egypt”  that  he  ordered  a gift  of  corn  to  Peter  Smith,  and  soon  thereafter  had  the 
name  of  his  plantation  and  the  little  settlement  changed  from  LaGrange  to  Egypt. 


THE  DEEP  BIVEK  COAL  FIELD 


15 


route  by  the  establishment  of  slack-water  navigation  on  Deep  and 
Cape  Fear  rivers,  and  (2)  by  railroad  to  Fayetteville  and  then  by 
barges  down  Cape  Fear  River  from  that  place  to  Wilmington.  The 
railroad  was  the  first  to  be  secured,  construction  beginning  at  Fayette- 
ville in  1855.  Egypt  was,  during  the  Civil  War,  the  western  terminus 
of  this  road  and  considerable  coal  mined  at  Farmville,  Egypt  and 
Gulf  was  shipped  to  Fayetteville  to  supply  the  arsenal  at  that  place 
or  to  be  transshipped  to  Wilmington  for  the  use  of  blockade  runners. 

The  building  of  locks  and  dams  to  secure  slack-water  navigation 
between  Fayetteville  and  Carbonton  was  begun  by  private  parties  about 
the  same  time  as  railroad  construction  was  begun,  but  it  resulted  in 
failure  and  the  State  took  over  the  project.  Just  as  the  locks  and 
dams  were  completed  war  broke  out  and  they  were  forgotten  in  the 
stress  of  wartime  conditions,  and  all  of  the  dams  went  out,  except 
the  Lockville,  Gorgas  and  Gulf  dams,  which  were  kept  up  to  supply 
water-power  for  grist  mills.  Upon  the  termination  of  the  war,  atten- 
tion was  again  attracted  to  the  need  of  slack-water  navigation  on  Deep 
River  and  the  Deep  River  Navigation  Company  was  organized  and 
began  rebuilding  the  locks  and  dams,  largely  for  the  purpose  of 
transporting  iron  ore  from  the  vicinity  of  Buckhorn  on  Cape  Fear 
River  to  the  Endor  furnace  on  Deep  River.  This  company  maintained 
locks  and  dams  on  Cape  Fear  River  at  Battles  and  Buckhorn  and  on 
Deep  River  at  Lockville,  Gorgas,  Endor  and  Gulf.  A dam  was  also 
built  at  Carbonton,  but  the  lock  was  never  used.  It  is  reported  that 
slack-water  navigation  was  carried  on  in  1873  and  for  several  years 
thereafter,  but  eventually  the  locks  and  dams  were  permitted  to  fall  into 
decay  as  the  iron  business  declined  and  finally  all  were  swept  out  of 
existence,  and  slack-water  navigation  on  Deep  River  was  a thing  of  the 
past. 

The  Egypt  mine  (PI.  Ill)  had  a checkered  history  after  the  Civil 
War;  ownership  changed  frequently,  but  no  one  seemed  to  be  able 
to  operate  at  a profit.  Finally  in  1870  the  mine  was  closed  down  and 
it  remained  flooded  until  1888  when  it  was  reopened,  but  with  no 
better  success  in  mining  and  marketing  the  coal  than  had  been 
attained  before.  The  mine  continued  in  operation  until  1902,  but 
owing  to  several  bad  explosions  of  gas  and  to  financial  difficulties  it 
was  again  closed  and  remained  under  water  until  1915.  At  the  last 
mentioned  date  the  property  passed  into  the  hands  of  the  Norfolk 
Southern  Railroad  Company  and  was  rehabilitated  under  the  name  of 
the  Cumnock  Coal  Company,  the  name  Egypt  being  no  longer  acceptable 
on  account  of  the  many  disastrous  explosions  that  had  occurred  in  the 
mine  when  it  was  operated  under  that  name.  From  1915  down  to  1922 


16 


THE  DEEP  RIVER  COAL  FIELD 


the  entire  output  of  Cumnock  mine  has  been  used  for  railroad  pur- 
poses, but  this  has  not  been  great,  as  the  mine  has  been  operated  in  only  a 
small  way.  In  September,  1922,  the  property  was  bought  by  the 
Erskine  Ramsey  Coal  Company  with  the  intention  of  greatly  enlarging 
the  mine  and  increasing  its  output. 

About  1921  the  Carolina  Coal  Company  was  organized  for  the 
purpose  of  developing  a mine  at  the  site  of  the  old  village  of  Farmville 
in  Chatham  County,  just  across  the  river  from  the  Cumnock  mine. 
The  company  began  the  shipment  of  coal  in  a small  way  in  the  summer 
of  1922  by  trucking  the  coal  to  the  railroad  at  Cumnock,  but  recently 
grading  has  been  done  for  a direct  connection  with  the  Norfolk  Southern 
Railroad  and  it  is  probable  that  by  the  time  this  report  goes  to  press 
the  rails  will  have  been  laid  and  all-rail  shipments  begun. 

The  entire  history  of  coal  mining  operations  in  the  Deep  River  Field 
has  been  one  of  many  failures,  due  to  lack  of  adequate  capital  to 
develop  a mine  under  the  mining  conditions  here  prevailing,  to  lack 
of  experience  in  coal  mining,  and  to  lack  of  adequate  transportation 
facilities  to  reach  the  consumers  who  were  located  mostly  on  the  sea- 
shore many  miles  distant.  Today  conditions  of  marketing  and  trans- 
portation are  very  different;  the  railroads,  the  cotton  mills,  and  other 
manufacturing  plants  are  ready  and  eager  for  fuel,  to  say  nothing 
of  the  thousands  of  homes  that  call  for  a domestic  supply,  and  as  the 
field  has  now  fairly  adequate  railroad  service,  there  seems  to  be  no 
reason  why  mining  operations  should  not  be  reasonably  successful 
provided  there  is  an  adequate  supply  of  coal  in  the  ground  that  can 
be  obtained  at  moderate  cost. 

The  Present  Investigation 

The  present  investigation  was  undertaken  with  the  idea  that  the  coal 
of  the  Deep  River  Field  is  much  more  valuable  than  has  been  generally 
believed  and  that  it  is  a source  of  fuel  for  the  mills  and  railroads  of 
Eastern  North  Carolina  if  it  could  be  demonstrated  that  there  is  large 
enough  tonnage  available  at  a reasonable  depth  to  warrant  the  invest- 
ment of  capital. 

It  was  fully  realized,  before  systematic  work  was  undertaken,  that 
exposures  of  coal  and  the  associated  rocks  are  poor  and  totally  inade- 
quate for  a minute  survey  of  the  field.  It  was  also  realized  that  most 
of  the  coal  prospects  had  been  opened  many  years  ago  and  that  almost 
without  exception  they  are  now  caved  so  that  the  coal  is  as  effectually 
concealed  as  if  mines  and  prospect  pits  had  never  been  opened. 

To  the  writers  it  seemed  possible,  however,  to  map  the  field  and 
determine  in  a general  way  whether  the  coal  is  lenticular  or  whether 


THE  DEEP  RIVER  COAL  FIELD 


17 


it  extends  indefinitely  along  the  belt  of  Triassic  rocks  as  well  as  across 
the  trough  toward  the  southeast.  It  also  seemed  possible,  by  careful 
field  observation  and  the  plotting  of  dips  to  determine  with  some  degree 
of  accuracy  the  shape  of  the  trough  and  also  the  depth  of  the  coal  at 
different  points  within  the  trough.  The  results  of  the  examination 
herewith  presented  are  far  from  satisfactory  to  the  writers,  but  they 
are  about  as  accurate  as  it  is  possible  to  make  them  without  deep  drilling 
in  the  interior  of  the  trough. 

GEOGRAPHY  OF  THE  DEEP  RIVER  COAL  FIELD 

The  Deep  River  coal  field,  as  outlined  on  the  accompanying  map, 
extends  from  a short  distance  northeast  of  Cape  Fear  River  in  a 
southwesterly  direction  to  Carthage  and  in  the  other  direction  from 
Sanford  on  the  southeast  to  a few  miles  beyond  Gulf  on  the  northwest. 
It  embraces  parts  of  Chatham,  Lee  and  Moore  counties.  It  has  long 
been  known  as  the  Deep  River  Coal  Field  because  almost  all  the  prospect- 
ing and  development  has  been  on  or  near  that  stream  from  near 
Glendon  to  the  point  where  Deep  and  Haw  rivers  unite  to  form  Cape 
Fear  River,  but  it  should  be  clearly  understood  that  the  presence  of 
coal  has  been  demonstrated  in  only  a small  part  of  the  area  outlined 
above. 

The  field  here  considered  lies  mainly  in  the  valley  of  Deep  River 
and  the  surface  consists  of  a number  of  low  plateaus  or  terraces  that, 
near  the  river  and  also  along  its  more  important  tributaries,  have  been 
sharply  dissected.  The  altitude  ranges  from  about  165  feet  above 
sea  level  at  Avants  Ferry  on  Cape  Fear  River  to  580  feet  on  the  ridge 
at  Carthage.  The  latter  is  the  highest  land  in  the  field  and  is  a narrow 
remnant  of  a plateau  that  was  doubtless  once  continuous  throughout 
this  part  of  the  State,  but  now  has  been  so  dissected  by  streams  that 
only  remnants  of  its  once  even  surface  remain  on  the  inter-stream  areas. 
On  the  southeastern  margin  of  the  field  the  coal-bearing  rocks  have 
been  in  places  deeply  covered  with  white  sand  which  prevents,  in  large 
measure,  dissection  by  the  streams  and  consequently  this  part  of  the 
field  consists  generally,  except  in  the  immediate  vicinity  of  the  larger 
streams,  of  an  undissected  plain  in  which  the  bed  rock  is  effectually 
concealed  by  the  imneer  of  white  sand. 

The  area  represented  by  the  map  is  essentially  an  agricultural 
country,  the  principal  crops  being  cotton  and  tobacco.  Recently  the 
raising  of  fruits  of  various  descriptions  has  become  quite  successful  in 
adjacent  areas  and  it  seems  probable  that  their  cultivation  may  extend 
into  this  district.  The  river  bottoms  are  particularly  fertile,  being 
almost  universally  cleared  and  in  a high  state  of  cultivation,  except 


Geol. — 2 


18 


THE  DEEP  RIVER  COAL  FIELD 


a deep  fringe  of  trees,  vines,  and  weeds  which  line  the  immediate  banks 
of  the  rivers,  as  shown  in  PL  2-A. 

The  highways  generally  follow  the  inter-stream  divides,  for  these, 
except  near  the  rivers,  are  generally  flat  and  well  suited  for  highway 
construction.  In  building  some  of  the  new  automobile  roads,  however, 
less  attention  is  paid  to  the  surface  features  and  the  roads  pursue 
more  direct  courses  than  would  be  possible  were  they  to  follow  the 
divide  between  streams.  The  railroads,  on  the  contrary,  generally 
follow  the  minor  drainage  lines  in  their  courses  across  the  major 
drainage  basins  of  the  region,  for  in  so  doing  they  secure  nearly  a 
water  grade. 

The  principal  railroad  in  the  field  is  the  main  line  of  the  Seaboard 
Air  Line  which  enters  the  field  from  the  north  near  Moncure,  passes 
south  through  Sanford  and  leaves  the  field  1 miles  west  of  Jonesboro. 
The  Atlantic  and  Yadkin  (a  branch  of  the  Southern  Railway)  extends 
southeastward  from  Greensboro  to  Sanford  where  it  terminates,  but 
through  passenger  trains  are  run  on  to  Wilmington  over  a branch  of 
the  Atlantic  Coast  Line.  The  Norfolk  Southern  Railroad  has  recently 
acquired  or  built  a line  running  southwestward  from  Raleigh  to 
Charlotte.  This  railroad  enters  the  Deep  River  Field  at  Corinth, 
east  of  Cape  Fear  River,  traverses  the  developed  coal  district  about 
Cumnock  and  Gulf  and  leaves  the  mapped  area  at  Putnam.  Two  small 
narrow-gauge  lines  also  serve  the  field : the  Atlantic  and  W estern 
from  Sanford  to  Broadway  and  Lillington;  and  the  Randolph  and 
Cumberland  through  Hallison,  Carthage,  and  Cameron.  Formerly  a 
narrow-gauge  branch  of  the  Norfolk  Southern  extended  from  Carthage 
to  Pinehurst,  but  train  service  had  been  abandoned  for  some  time  when 
the  present  field  examination  was  made. 

The  Deep  River  Coal  Field  lies  near  the  center  of  the  State,  being 
about  45  miles  southwest  of  Raleigh,  60  miles  southeast  of  Greensboro, 
125  miles  east  of  Charlotte,  35  miles  northwest  of  Fayetteville,  and  30 
miles  north  of  Southern  Pines  and  Pinehurst.  Sanford,  the  principal 
town,  is  situated  on  the  main  artery  of  automobile  travel  from  Washing- 
ton and  Richmond  to  the  winter  resorts  of  the  South  and  it  also  has 
good  automobile  roads  leading  to  the  more  important  cities  and  towns 
in  the  surrounding  region. 

GEOLOGIC  FORMATIONS 

General  Statement 

The  sandstone  and  shale  which  are  associated  with  the  coal  beds  in 
the  Deep  River  Field  extend  in  a narrow  belt  of  outcrop  nearly  across 
the  State  in  a north-south  direction.  This  belt  begins  in  a point  *in 


PLATE  II 


A.  Deep  River  from  the  Horseshoe  Bridge.  The  bottom  on  the  left  is  cleared 
and  farmed,  except  for  a fringe  of  trees  and  vines  on  the  river  bank. 


B.  Outcrop  of  the  Cumnock  coal  bed  near  Gulf.  This  outcrop,  in  a recent  cut 
made  by  the  Norfolk  Southern  Railroad,  shows  about  4 feet  of  badly  watered 


THE  DEEP  RIVER  COAL  FIELD 


19 


the  vicinity  of  Oxford  in  Granville  County  and  extends  southwestward 
through  the  towns  of  Durham,  Sanford,  and  Carthage,  about  as  shown 
on  Kerr’s1  geologic  map  of  the  State  to  beyond  Wadesboro,  where  it 
crosses  into  South  Carolina  near  its  southern  terminus. 

There  has  been  much  written  on  the  subject  of  the  geologic  age  of 
these  rocks,  which,  according  to  the  fossil  remains  found  in  them, 
appears  to  have  been  well  determined.  The  writers,  during  the  course 
of  the  present  investigation,  gave  no  attention  to  this  phase  of  the 
subject,  accepting  the  usage  current  in  geologic  literature. 

The  red  sandstone  of  the  Connecticut  Valley  in  Connecticut  and 
Massachusetts;  the  great  belt  of  red  sandstone,  shale  and  trap  rock 
extending  from  the  Hudson  River  to  Culpepper,  Virginia;  the  Rich- 
mond, Earmville,  and  other  scattered  areas  of  similar  rocks  in  Virginia; 
and  the  rocks  of  the  Dan  and  Deep  River  fields  of  North  Carolina  all 
are  of  Triassic  age  and  belong  to  what  geologists  call  the  Newark  group, 
a name  given  to  them  by  W.  C.  Redfield,  because  of  their  excellent 
development  in  the  vicinity  of  Newark,  N.  J.  Redfield  introduced 
the  name  as  follows  :2 

I propose  the  latter  designation  [Newark  group]  as  a convenient  name  for 
these  rocks  [red  sand  stones  and  shales  of  New  Jersey  and  Eastern  Pennsyl- 
vania], and  those  of  the  Connecticut  Valley,  with  which  they  are  thoroughly 
identified  by  foot  prints  and  other  fossils,  and  I would  include  also  the  con- 
temporary sandstones  of  Virginia  and  North  Carolina. 

Later  I.  C.  Russell3  definitely  applied  the  term  Newark  group  to  the 
rocks  of  both  the  Dan  and  the  Deep  River  fields  of  North  Carolina 
with  the  idea  that  possibly  future  workers  might  subdivide  the  group 
into  a number  of  formations. 

In  the  Deep  River  Field  geologists  have  recognized  certain  differences 
in  the  rocks,  some  of  the  rocks  being  distinctly  red  and  others  being 
generally  drab  or  gray,  but  no  one,  with  the  exception  of  Ebenezer 
Emmons,  one  of  the  former  State  geologists,  has  definitely  attempted 
to  map  such  distinctions  and  to  give  them  specific  names.  Emmons, 
in  his  report  of  1852  (p.  120),  refers  to  the  various  divisions  of  the 
Newark  group  as  follows: 

The  coal  seams  of  Deep  River  may  be  described  under  three  grand  divisions, 
proceeding  from  the  inferior  to  the  superior  beds : 

1.  Inferior  conglomerates  and  sandstones  below  the  green  and  black  slates. 

2.  Black  slates,  with  their  subordinate  beds  and  seams. 

3.  Sandstones,  soft  and  hard,  with  freestone,  grindstone  grits,  and  superior 
conglomerates. 

HCerr,  W.  C.  : Report  of  the  Geological  Survey  of  North  Carolina,  vol.  1,  Raleigh,  1875. 

-’The  name  Newark  as  applied  to  a geological  formation  was  proposed  by  W.  C.  Redfield 
in  a paper,  “On  the  relations  of  the  fossil  fishes  of  the  sanustone  of  Connecticut  and  other 
Atlantic  States  to  the  Triassic  and  Colitic  periods.”  Am.  Jour.  Sci.,  2d  series,  vol.  22, 
pp.  357,  1856,  and  Prac.  Am.  Asso.  Adv.  Sci.,  vol.  10,  pp.  181,  1856. 

3Russell,  I.  C.  : Correlation  papers — the  Newark  system.  U.  S.  Geological  Survey, 

bulletin  85,  1892. 


20 


THE  DEEP  RIVER  COAL  FIELD 


In  his  report  of  1856  (p.  228),  Emmons  recognizes  in  his  text  the 
three  divisions  enumerated  in  his  earlier  paper,  for  he  says: 

A natural  division  seems  to  exist  when  we  take  into  account  the  physical 
characters  of  the  formation  only ; and  indeed  it  would  be  disregarding  im- 
portant features,  were  these  to  be  passed  by  unnoticed.  According  then  to 
these  features,  the  series  should  be  divided  into  three  great  deposits,  the  lower 
red  sandstone  and  its  conglomerate ; the  coal  measures  including  slates,  shales 
and  drab-colored  sandstones,  with  their  subordinates ; and  lastly,  the  upper 
red  sandstones  and  marls. 

But  on  the  map  accompanying  this  report  he  represents  four  divisions 
in  the  Newark  group,  as  follows : 

(4)  Upper  sandstone. 

(3)  Salines.1 

(2)  Coal  slate  and  coal. 

(1)  Lower  sandstone. 

Although  Emmons  shows  the  four  divisions  on  his  sketch  map  in 
the  report  for  1856,  it  is  doubtful  if  he  could,  in  the  field,  generally 
distinguish  the  “Coal  slate  and  coal”  from  the  “Salines,”  the  latter 
being  simply  drab  shale,  above  the  coal  in  the  Cumnock  shaft,  which, 
because  of  the  salt  that  it  contains,  can  there  he  readily  separated  from 
the  underlying  coal-bearing  rocks.  The  writers  made  no  attempt  to 
differentiate  the  “Salines”  from  the  “Coal  slate  and  coal,”  for  it  seems 
extremely  doubtful  if,  in  the  weathered  exposures  generally  found  in 
the  field,  the  two  phases  could  he  identified  and  differentiated. 

The  Newark  group  in  the  Deep  Iiiver  Field  consists  of  three  generally 
recognizable  parts,  by  geologists  called  formations;  a lower  formation 
composed  largely  of  red  and  brown  sandstone,  a middle  formation  of 
light-colored  or  drab  shale,  sandstone  and  coal  beds;  and  an  upper 
formation  of  mainly  red  conglomerate  of  great,  though  unknown  thick- 
ness. In  places  these  formations  are  clearly  marked  and  easily  followed 
on  the  surface,  but  in  other  places  the  middle  formation  disappears, 
being  either  faulted  out  or  replaced  by  red  sandstone  or  conglomerate 
similar  to  that  in  the  other  formations.  As  it  is  desirable  to  map  and 
describe  these  formations,  it  seems  best  to  give  them  specific  names 
so  as  to  simplify  the  descriptions  and  the  reference  to  the  formations 
as  much  as  possible.  In  accordance  with  this  idea,  the  name  Pekin  is 
selected  for  the  lowest  formation,  Cumnock  for  the  middle  formation, 
and  Sanford  for  the  upper  formation.  The  reasons  for  the  selection 
of  these  names  will  be  given  under  the  description  of  each  of  the 
formations.  In  the  following  description  the  formations  will  be  con- 

VThrough  an  obvious  error  in  preparing  the  geologic  map  for  this  report  the  “Salines” 
was  placed  below  the  “Coal  slate  and  coal.” 


THE  DEEP  BIVER  COAL  FIELD 


21 


sidered  in  ascending  order,  beginning  with  the  lowermost  one  which  was 
laid  down  probably  on  a land  surface  of  the  ancient  crystalline  schist 
and  slate. 

Pekin  Formation 

IN" o specific  name  has  heretofore  been  applied  to  the  lowermost  forma- 
tion of  the  Newark  group  in  this  field;  it  has  generally  been  referred 
to  as  the  “Lower  red  sandstone.”  As  it  is  one  of  the  most  definite 
formations  of  the  group,  it  seems  best  to  propose  a geographical  name 
for  it.  Unfortunately  the  names  of  the  towns  situated  on  the  outcrop 
of  this  formation  in  the  Deep  River  Coal  Field  are  either  in  current  use 
for  other  formations  in  nearby  states,  or  the  formation  at  the  particular 
place  does  not  show  in  typical  form,  hence  no  name  within  this  field 
is  suitable. 

At  the  close  of  geologic  work  in  the  area  here  considered,  the  writers 
made  a hurried  examination  of  the  Newark  formations  in  Montgomery 
and  Randolph  counties.  In  this  reconnaissance  the  succession  of  rocks 
in  the  group  was  found  to  be  identical  with  that  observed  in  the  Deep 
River  Field.  The  lowermost  formation  is  prevailingly  red  and  occupies 
a belt  of  outcrop  about  2 miles  in  width  on  the  northwest  side  of  the 
trough  of  Newark  rocks;  this  is  succeeded  by  the  overlying  light  and 
black  shales  of  the  Cumnock  formation.  The  best  exposure  of  the 
lowermost  formation  was  seen  on  the  road  running  due  east  from  Mt. 
Gilead.  This  road  crosses  Little  River  4 miles  to  the  east  and  on  the 
second  terrace  about  one-half  mile  east  of  the  river  the  red  sandstone 
of  the  Newark  appears.  The  road  continues  on  this  rock  for  a distance 
of  2 or  21/o  miles  and  then  passes  onto  the  characteristic  light-colored 
rocks  of  the  Cumnock  formation.  In  the  midst  of  the  lower  red  rocks 
is  the  village  of  Pekin,  and  it  is  proposed  to  call  the  lowermost  red 
sandstone  and  shale  Pekin  for  this  place,  as  the  formation  here  is  in 
typical  form. 

In  the  Deep  River  Coal  Field  the  Pekin  formation  shows  in  outcrop 
in  a belt  of  fairly  even  width  but  more  or  less  broken  because  of 
inability  of  the  writers  to  recognize  in  places  the  overlying  Cumnock 
formation,  from  the  Carthage-Charlotte  road  on  the  southwest  to  Cum- 
nock, and  in  a much  narrower  belt  8 miles  or  so  northeast  to  Moncure 
on  Deep  River.  Professor  Emmons  appears  to  have  been  the  first 
person  to  assign  a thickness  to  the  lower  sandstone.  His  original  state- 
ment (Report  of  1852,  p.  137)  is  as  follows: 

The  inferior  mass  or  that  below  the  slate,  is  about  fifteen  hundred  [feet] 


22 


THE  DEEP  KIVER  COAL  FIELD 


In  his  later  and  more  comprehensive  report  (Report  of  1856,  p.  231), 
Emmons  revises  his  figures  to  some  extent,  as  follows : 

The  thickness  of  the  lower  red  sandstones  at  the  Gulf  and  Egypt  [Cumnock] 
is  at  least  fifteen  hundred  feet,  and  probably  nearer  two  thousand. 

Other  writers  on  this  field  generally  give  the  thickness  of  these 
sandstones  as  1,500  or  1,600  feet,  apparently  accepting  the  estimate  of 
Emmons  as  given  above. 

During  the  course  of  the  present  examination  almost  all  roads 
crossing  the  Pekin  formation  were  carefully  surveyed  by  plane-table 
and  telescopic  alidade,  distances  being  measured  by  stadia.  As  the 
survey  progressed  most  of  the  outcropping  rocks  were  noted  and  dips 
and  strikes  recorded  in  their  proper  positions  on  the  plane-table  sheet. 
Cross-sections  of  the  Pekin  formation  made  up  from  these  data  give 
fairly  accordant  results,  as  far  as  the  best  sections  are  concerned,  of 
about  2,000  feet.  This  thickness  was  obtained  on  the  new  Carthage- 
Charlotte  highway  near  Calvary  Church,  on  the  road  running  north- 
westward from  Carbonton,  and  on  the  road  running  north  from  the 
bridge  over  Deep  River  at  Cumnock. 

In  that  part  of  the  field  north  and  east  of  Colon,  the  upper  limit  of 
the  Pekin  formation  was  not  definitely  determined,  as  the  light-colored 
shale  and  sandstone  which  carry  coal  beds  appear  to  be  poorly  developed 
and  it  was  impossible  to  trace  them  continuously  and  determine  the 
contact  between  them  and  the  Pekin  formations,  but  in  a general  -way 
as  far  as  Deep  River  the  Pekin  formation  appears  to  be  much  thinner 
than  it  is  farther  south.  A rough  measure  north  of  Zion  Church  shows 
a thickness  of  about  1,000  feet  and  a similar  thickness  seems  to  he 
present  at  Rockville  at  the  crossing  of  Deep  River. 

East  of  Deep  River  the  contact  of  the  Pekin  formation  and  the 
ancient  schist  makes  a turn  toward  the  northwest  nearly  at  right  angles 
to  its  previous  course,  and  north  of  Moncure  these  beds  appear  to  regain 
their  normal  thickness  of  about  2,000  feet.  The  reason  for  this  abrupt 
change  in  direction  of  the  line  of  contact  was  not  apparent  in  the  field, 
hut  it  may  be  due  to  great  irregularities  in  the  surface  on  which  the 
Pekin  formation  was  deposited.  Emmons  in  his  report  of  1856  (pp. 
231-232)  noted  the  extreme  thinness  of  the  Pekin  formation  at  Jones’ 
Palis  (Rockville).  He  reports  less  than  40  feet,  hut  he  offers  no  adequate 
explanation  of  the  anomalous  conditions  which  reduced  it  to  this  thick- 
ness. He  interprets  the  great  mass  of  conglomerate  which  the  writers 
saw  on  the  railroad  north  of  Moncure  as  an  overlap  of  the  upper  red 
sandstone  across  the  eroded  edge  of  the  light-colored  shale,  but  this 
can  hardly  he  the  case  as  the  belt  of  outcrop  of  the  light-colored  beds 


THE  DEEP  RIVER  COAL  FIELD 


23 


is  continuous  and  the  rocks  are  well  exposed  on  the  Capital  Highway 
in  the  north  edge  of  the  village. 

The  most  remarkable  member  of  the  Pekin  formation  is  a gray 
conglomerate  composed  of  white  quartz  pebbles  ranging  up  to  2 inches 
in  diameter.  This  bed  is  hard  and  very  resistant  and  has  been  exten- 
sively quarried  iu  the  past  for  millstones.  It  is  the  basal  conglomerate 
of  the  Pekin  formation  and  was  laid  down  on  the  eroded  edges  of  the 
ancient  schist  and  slate  which  form  the  basement  complex  of  the 
region.  The  pebbles  were  doubtless  derived  from  quartz  veins  that  are 
of  common  occurrence  in  the  underlying  rocks.  They  are  well  rounded 
and  show  by  their  shape  that  they  have  been  rolled  for  a considerable 
distance  by  a fairly  rapid  stream  of  water.  The  matrix  also  consists 
of  the  same  material  reduced  to  a still  finer  condition. 

The  millstone  conglomerate  is  found  in  its  best  development  on  the 
northwest  border  of  the  field  from  the  Carthage-Charlotte  highway 
northeastward  to  the  vicinity  of  Putnam.  It  was  also  noted  by  the 
writers  on  the  east  side  of  Deep  River  southeast  of  the  Carolina  coal 
mine,  and  fragments  were  found  on  the  west  side  of  the  river  north  of 
the  coal  mine.  This  rock  was  in  great  demand  in  the  early  days  for 
the  manufacture  of  millstones,  and  quarries  were  opened  at  many 
places  on  its  outcrop.  The  largest  operation  of  this  kind,  the  ruins  of 
which  were  seen  by  the  writers,  was  on  McCallum  Fork  of  Richland 
Creek,  about  300  feet  below  the  crossing  of  the  highway  that  connects 
Calvary  Church  with  Ilallison  and  Putnam.  Here  there  was  a large 
quarry  from  which  the  raw  material  was  obtained,  and  an  extensive 
plant  for  the  shaping  of  the  raw  material  into  the  finished  product. 
Trees  have  completely  overgrown  the  ruined  mill  and  office  and  water 
has  flooded  the  quarry,  so  that  little  now  remains  to  mark  the  site  of 
a once  flourishing  industry. 

The  quarry  noted  above  is  certainly  100  years  old,  as  it  is  described 
by  Professor  Olmsted  in  his  report  (p.  15)  of  1824,  as  follows: 

The  region  of  sandstone  embraces  several  beds  of  that  conglomerate  rock 
which  is  used  for  millstones.  But  the  most  distinguished  locality  for  the 
millstone  grit  occurs  on  Richland  Creek  in  Moore  County,  near  the  west- 
ern limit  of  the  formation.  . . . This  excellent  bed  of  millstone  grit 

is  exposed  to  view  directly  on  the  bank  of  the  creek,  forming  three 
horizontal  strata  or  layers,  each  composed  of  large  tabular  masses.  The  lowest 
stratum  is  the  best  quality  for  millstones.  It  consists  of  a hard  grayish  red 
sandstone  in  which  are  thickly  imbedded  water-worn  pebbles  of  white  flint 
or  quartz.  These  millstones  are  very  much  valued  for  grinding  coni,  and  are 
sought  for  from  distant  parts  of  the  State,  and  bring  from  $30  to  $100  per  pair. 

Chance  in  his  report  of  1885  (p.  24)  makes  the  following  statement  : 

In  Moore  County  the  conglomerate  at  the  base  of  the  formation  yields  an 
excellent  stone  for  corn-mills.  A factory  has  recently  been  established  by 


24 


THE  DEEP  RIVER  COAL  FIELD 


the  North  Carolina  Millstone  Co.,  and  complete  mills  ready  for  the  belt  are 
now  made  and  shipped  in  large  numbers. 

This  conglomerate  was  also  found  on  the  east  bank  of  Deep  River 
where  it  is  cut  by  the  Deep  River  fault,  about  a mile  east  of  the  old 
Endor  iron  furnace.  It  was  not  seen  northeast  of  that  place,  although 
the  base  of  the  Pekin  formation  was  crossed  at  a number  of  places. 

At  Rockville,  a coarse  conglomerate  occurs  on  both  sides  of  Deep 
River  at  what  appears  to  be  the  same  horizon  as  that  of  the  millstone 
grit,  but  here  the  matrix  is  a strong  red  color  and  the  pebbles  or  rather 
the  boulders — for  they  range  up  to  at  least  twelve  inches  in  diameter — 
are  of  schist.  The  rock  bears  no  resemblance  to  the  white  quartz 
conglomerate  of  the  millstone  grit,  although  it  seems  to  be  at  that 
horizon.  The  red  conglomerate  is  well  shown  in  the  cuts  of  the  Capital 
Highway  where  this  road  climbs  to  the  upland  south  of  the  river  and 
it  was  also  seen  in  full  force  on  a branch  of  the  Seaboard  Air  Line 
Railway  which  runs  due  north  from  Moncure  to  Pittsboro.  Curiously 
enough,  however,  this  conglomerate  does  not  show  on  the  main  automo- 
bile road  to  Pittsboro  which  turns  to  the  left  about  one-quarter  of  a 
mile  beyond  Lockport.  On  this  road  the  schist  makes  its  appearance 
in  less  than  one-half  mile  and  from  that  point  for  about  one-quarter 
of  a mile  the  road  runs  practically  on  the  contact  of  the  red  schist 
conglomerate  and  the  underlying  bed-rock. 

Professor  Emmons  noted  (report  of  1856,  p.  237)  this  appareut 
thinning  of  the  Pekin  formation  at  Jones’  Falls  (now  Lockport)  and 
the  presence  of  the  red  conglomerate  noted  above,  but  instead  of  regard- 
ing the  conglomerate  as  the  basal  member  of  the  Pekin  formation,  he 
considered  it  as  belonging  to  the  red  sandstones  of  the  Sanford  forma- 
tion. He  accounted  for  its  present  position  as  being  due  to  uncon- 
formable  deposition  across  the  eroded  edges  of  the  Cumnock  formation. 
Professor  Emmons  proved  his  case,  as  he  supposed,  by  the  discovery 
of  certain  fossil  plants  above  the  schist  conglomerate  near  Rockville 
and  by  the  finding  on  Haw  River  of  the  same  fossil  plants  overlying 
one  of  the  conglomerate  beds  of  the  Sanford  formation.  Whether  or 
not  Professor  Emmons  is  correct  in  attributing  the  presence  of  this 
schist  conglomerate  in  contact  with  the  schist  itself  as  due  to  overlap 
the  writers  cannot  affirm  or  deny,  as  time  did  not  permit  of  a close 
examination  of  the  rocks  or  of  the  collecting  of  fossils  from  them. 
In  some  respects  Emmons’  theory  seems  to  apply,  hut  in  others  it  is 
contrary  to  the  observed  facts.  The  writers  are  not  in  a position  to 
settle  this  question,  so  merely  call  attention  to  it  as  one  of  the  interesting 
points  that  future  workers  may  look  forward  to  as  a problem  worthy 
of  their  best  efforts. 


THE  DEEP  RIVER  COAL  FIELD 


25 


The  other  members  of  the  Pekin  formation  are  fairly  uniform  in 
character  throughout  the  field  and  have  no  striking  characteristics  that 
call  for  comment.  Professor  Emmons’  description  of  the  rocks  com- 
posing this  formation  is  very  good  and  the  writers  can  add  little  or 
nothing  to  it,  except  that  in  places  the  formation  carries  considerable 
hematite  which  appears  to  be  very  pure,  and,  if  it  could  be  found  in 
great  quantity,  would  be  extremely  valuable  as  an  ore  for  iron-making. 
An  exposure  of  this  hematite  was  found  in  a cut  of  the  Norfolk  Southern 
Railroad  about  a half  a mile  northwest  of  the  station  of  Colon.  This 
occurs  as  a mass  about  five  feet  long  and  one  foot  broad  and  of  unknown 
depth ; it  is  in  sandy  shale  which  strikes  nearly  east-west  and  dips 
twenty-six  to  thirty  degrees  to  the  south.  Similar  masses,  though  of 
smaller  dimensions,  were  seen  in  the  clay  pit  of  the  brick  works  at 
Colon  in  shale  that  also  appears  to  dip  to  the  south.  If  the  dip  and 
strike  are  at  all  indicative  of  the  general  geologic  structure,  this  shale 
belongs  in  the  Pekin  formation  and  underlies  the  Cumnock  formation 
which  outcrops  farther  to  the  south.  The  iron  ore  exposed  in  the 
vicinity  of  Colon  is  doubtless  of  secondary  origin  and  due  to  the  segre- 
gation of  iron  in  the  deeply  oxidized  shale  and  shaly  sandstone.  All 
of  the  red  rocks  of  the  Newark  group  contain  much  iron,  but  until 
segregation  takes  place,  the  iron  is  too  widely  disseminated  to  be  of 
value  as  an  ore. 

Cumnock  Fosmation 

General  Statement.  The  coal-bearing  rocks  are  not  so  well  exposed 
as  are  those  belonging  to  the  Pekin  formation.  In  fact,  were  it  not 
for  the  section  in  the  mine  shaft  at  Cumnock,  geologists  would  have  a 
very  inadequate  idea  of  the  composition  of  the  coal-bearing  formation 
in  this  field.  Because  the  shaft  section  is  regarded  as  the  type  of  the 
formation  and  because  the  development  of  the  coal  has  been  much  more 
extensive  here  than  at  any  other  place  in  the  field,  the  name  Cumnock 
is  given  to  the  generally  light-colored  rocks  bearing  coal  or  associated 
with  the  coal.  The  Cumnock  formation  varies  greatly  in  thickness  and 
composition  throughout  that  part  of  the  field  examined  so  that  it  is 
doubtful  if  the  section  exposed  in  the  Cumnock  mine  will  hold  in  distant 
localities. 

The  Egypt  (now  Cumnock)  shaft,  shown  on  PI.  Ill,  was  sunk, 
according  to  Captain  Charles  Wilkes1  of  the  United  States  Navy,  by 
the  Governor’s  Creek  Coal  and  Iron  Company,  but  local  information 
gathered  in  the  field  indicates  that  the  shaft  was  sunk  by  Brooks 
Harris  in  1852,  and  that  Harris  in  1853,  disposed  of  his  interest  in 

1Report  on  the  examination  of  the  Deep  River  district,  North  Carolina  Senate,  Doc. 
26,  35th  Congress,  2d  Sess.,  p.  6,  1859. 


26 


THE  DEEP  RIVER  COAE  FIELD 


the  property  to  Thomas  Andrews,  who,  in  the  same  year  organized  the 
Governor’s  Creek  Steam  Transportation  and  Mining  Company.  The 
geologic  world  is  greatly  indebted  to  Captain  Wilkes  for  preserving 
a record  of  the  rocks  penetrated  by  this  shaft,  for,  so  far  as  the  writers 
are  aware,  his  is  the  only  report  in  which  the  original  section  was 
published  and  even  the  present  owners  of  the  property  have  no  other 
record  than  that  given  in  Captain  Wilkes’  report. 

Emmons’  description  (Report  of  1856,  pp.  232-234)  of  the  Cumnock 
formation  and  its  thickness  and  component  parts  is  somewhat  vague 
and  indefinite  and  the  writers  are  not  satisfied  that  they  have  correctly 
interpreted  his  statements.  He  apparently  divides  the  coal  measures 
into  two  parts:  (1)  the  black  and  green  beds  of  the  bottom  and,  (2) 
drab-colored  beds  at  the  top.  The  thickness  of  the  former  is  given 
as  extending  150  to  200  feet  above  the  top  of  the  Cumnock  shaft 
section  and  200  feet  below  its  base.  This  would  give  the  black  and 
green  beds  a thickness  of  about  800  feet.  The  drab-colored  beds  he 
states  are  1,200  feet  thick  on  Mclver’s  plantation  near  Egypt.1  These 
measurements  give  a total  thickness  of  about  2,000  feet,  but  Emmons 
states  clearly  that  the  formation  is  probably  thicker  at  Egypt  than  it 
is  at  any  other  place  in  the  field. 

In  comparatively  recent  years  four  core-drill  holes  have  been  put 
down  to  the  Cumnock  coal  bed  on  the  Cumnock  property,  and  as  one  of 
these  holes  penetrated  the  coal  bed  at  a depth  of  1,064  feet  7 inches  it 
affords  an  even  better  section  than  that  revealed  by  the  Egypt  shaft. 
The  logs  of  these  four  wells  and  also  the  section  of  the  Egypt  shaft, 
as  given  by  Capt.  Wilkes,  are  shown  on  Eigure  1. 

In  borehole  Ho.  1 the  lowest  red  rock  penetrated  by  the  drill  is 
548  feet  above  the  Cumnock  coal  bed;  in  borehole  Ho.  2 it  is  561  feet; 
and  in  borehole  Ho.  3,  506  feet.  The  average  of  these  measurements 
is  538  feet.  If  all  the  exposures  in  the  field  were  as  clear  as  the  logs 
if  the  boreholes  there  would  seemingly  be  little  difficulty  in  determining 
;he  top  of  the  Cumnock  formation,  but  in  deeply  weathered  rocks  it  is 
not  always  possible  to  distinguish  brown  from  gray  unless  both  rocks 
are  strongly  marked.  Judging  from  the  experience  of  the  writers  in 
the  field,  it  seems  highly  probable  that  the  brown  sandstones  and  shales 
noted  in  logs,  1,  2,  and  3 (see  Fig.  1)  are  in  reality  included  in  the 
Cumnock  formation,  and  that  as  so  constituted,  it  extends  800-850  feet 
above  the  Cumnock  coal  bed  and  from  100  to  150  feet  below  that  bed. 
On  this  assumption  the  Cumnock  formation  at  the  Cumnock  mine  is 
about  1,000  feet  thick,  instead  of  2,000  feet,  as  determined  by  Emmons. 

xIt  is  possible  that  Emmons  intended  this  measurement  of  1.200  feet  to  include  the 
rocks  showing  in  the  Egypt  shaft.  If  so,  it  would  represent  the  full  thickness  of  the 
Cumnock  formation,  and  would  be  more  nearly  in  accord  with,  but  still  thicker  than, 
thicknesses  determined  in  surrounding  acres.  The  statements,  however,  are  too  vague 
to  be  taken  seriously. 


THE  DEEP  RIVER  COAL  FIELD 


27 


The  writers  endeavored  to  apply  the  Cumnock  shaft  section  to  the 
same  belt  of  rocks  observed  in  other  parts  of  the  field,  but  there 
seems  to  be  little  or  no  agreement  in  the  thickness  of  either  the  forma- 
tion as  a whole,  or  its  various  members.  In  fact  in  several  places  the 
formation  appears  to  be  lacking,  either  faulted  out  or  replaced  by  red 
conglomerate  similar  to  that  which  constitutes  the  major  part  of  the 
Sanford  formation  overlying  the  coals. 

Emmons,  in  his  report  of  1856,  states  that  he  experienced  difficulty 
in  tracing  the  belt  of  drab  sandstone  and  shale  which  constitute  the 


Egypt  shaft 


cumnqCk  mine 


Coal 
2'- 2" 


Shah'Sandy  S " 
Shale,  black  6" 
Coal,  bony  4-" 
31ackband 
/O" 

Coal 

/-6“ 

Shale  ,hlack  6" 


Analysis  8559b 


Analysis  85590 
3 kia/ys  is  B553A- 


Fig.  1.  Section  of  the  Cumnock  formation,  as  exposed  in  the  Cumnock  shaft  and  in 
boreholes  on  the  Cumnock  property. 


upper  part  of  the  Cumnock  formation.  He  attributed  the  apparent  vari- 
ation in  thickness  and  even  the  absence  of  the  coal-bearing  rocks  in  cer- 
tain places  to  an  unconformity  at  the  top  of  the  drab  member  (Cumnock 
formation)  which  allowed  the  lowest  bed  of  the  upper  red  sandstone 
to  overlap  and  conceal  a part  or  the  whole  of  the  coal-bearing  member. 
The  present  writers  looked  in  vain  for  indications  of  such  an  overlap, 


28 


THE  DEEP  RIVER  COAL  FIELD 


but  none  was  found,  and  they  came  to  the  conclusion  that  the  apparent 
thinning  and  even  disappearance  of  the  Cumnock  formation  could  he 
explained  in  another  way  which  seems  to  agree  with  observed  facts 
better  than  does  the  theory  that  Emmons  advanced.  The  theory  adopted 
by  the  present  writers  is  that  the  difference  in  the  formation  is  due  in 
large  part,  if  not  wholly,  to  variations  in  sedimentation  and  conse- 
quently, red  shale,  sandstone  or  even  conglomerate  may  have  been  laid 
down  in  one  part  of  the  field  at  the  same  time  that  drab  shale  or  even 
shale  containing  much  black  carbonaceous  matter  was  being  deposited 
in  another  part.  In  fact  it  seems  much  more  reasonable  and  in  accord 
with  observed  facts  to  assume  that  coal-forming  swamps  were  of  local 
occurrence  in  Triassic  time  in  much  the  same  manner  as  they  are 
limited  today  and  that  a swamp  extensive  enough  to  cover  North 
Carolina  from  north  to  south  is  much  less  probable  than  one  five,  ten, 
or  even  twenty  miles  in  extent. 

In  order  to  present  some  of  the  evidence  regarding  the  variation 
of  the  Cumnock  formation  in  this  field  it  will  first  be  necessary  to 
describe  the  distribution  of  the  outcrop.  Before  beginning  such  a 
description  it  is  well  to  explain  that,  although  the  territory  covered 
by  the  writers,  as  shown  on  the  map,  extends  from  Carthage  to  beyond 
Haw  River,  much  of  this  area  was  examined  in  a reconnaissance  manner 
only,  in  order  to  determine  the  general  structure  and  that  detailed 
examination  was  limited  to  localities  where  the  prospect  of  finding  coal 
in  commercial  quantity  is  more  promising  than  it  is  in  most  of  the  area 
represented  on  the  map.  The  description  begins  at  the  southwest 
extremity  of  the  area  and  extends  northeastward  to  the  farthest  point 
examined  in  the  vicinity  of  Moncure. 

In  the  Carthage  Trough.  On  the  new-cut  highway  which  extends 
northwestward  from  Carthage  the  rocks  are  excellently  exposed  from 
a point  about  IV2  miles  west  of  the  courthouse  at  Carthage  to  the 
northwestern  margin  of  the  field.  The  rocks  as  far  as  the  crossing  of 
Richland  Creek  are  prevailingly  red  and  as  they  dip  continuously  to 
the  southeast,  they  without  doubt  belong  to  the  Sanford  formation. 
The  red  rocks  continue  beyond  the  creek  for  a distance  of  about  400 
feet  where  they  rest  conformably  upon  light-colored  rocks  of  the  Cum- 
nock formation.  These  rocks  extend  along  the  highway,  except  where 
they  are  cut  by  a large  dike  near  the  middle  of  the  belt,  for  a distance 
of  2,200  feet,  and  to  all  appearances  they  are  conformable  and  the  full 
thickness  of  the  formation  is  present.  The  rocks  near  the  dike  are 
somewhat  disturbed,  but  beyond  its  influence  they  dip  with  considerable 
regularity  sixteen  degrees  to  the  southeast.  This  dip,  if  it  were  regular 
throughout  the  entire  formation  would  indicate  a thickness  of  only 


PLATE  III 


B.  The  Cumnock  coal  mine. 


THE  DEEP  KIVER  COAL  FIELD 


29 


600  feet.  As  this  measurement  is  much  less  than  that  obtained  a few 
miles  to  the  north,  as  explained  on  another  page,  one  is  forced  to  the 
conclusion  that  either  the  Cumnock  formation  is  here  unusually  thin 
or  that  it  has  been  cut  by  a fault  and  part  of  the  formation  has 
disappeared  in  the  process.  The  fault-hypothesis  seems  hardly  tenable 
as  in  other  longitudinal  faults  of  considerable  magnitude  in  this  region 
the  movement  has  been  such  as  to  duplicate  a part  or  all  of  the  outcrop 
and  thus  give  it  a greater  width  and  the  formation  an  apparently 
greater  thickness  than  it  normally  has  rather  than  to  reduce  the  width 
of  its  outcrop. 

The  rocks  exposed  are  principally  gray  sandstone  and  drab  shale, 
but  near  the  dike  the  shale  has  been  baked  to  a dark,  almost  black 
color  resembling  black  carbonaceous  shale.  No  sign  of  coal  was  observed 
but  reports  are  current  that  coal  has  been  seen  in  Richland  Creek 
somewhere  in  this  vicinity.  It  is  possible  that  coal  is  present  here, 
for  it  is  only  eight  and  one-half  miles  in  a direct  line  to  the  old  coal 
mine  on  the  Jones’  farm  east  of  Glendon,  but  whether  or  not  the  coal 
is  of  workable  thickness  here  is  another  problem  that  can  be  solved 
only  by  prospecting  with  pick  and  shovel,  or  with  a core  drill. 

The  next  line  of  observation  is  along  the  public  road  from  Mooshaunee 
to  Friendship  Church.  As  this  road  has  never  been  improved  there  are 
few  exposures,  but  so  far  as  the  surface  indications  go,  there  is  no 
evidence  that  the  Cumnock  formation  crosses  this  road.  The  same 
condition  holds  on  all  of  the  roads  crossing  the  territory  west  of 
McLennon’s  Creek  and  for  a distance  of  five  miles  northeast  of  the 
Randolph  and  Cumberland  Railroad.  This  country  was  crossed  on 
the  road  leading  to  the  southeast  from  Putnam,  also  on  the  road  running 
in  a similar  direction  from  Cool  Springs  Church,  and  on  a road 
intermediate  between  the  two.  On  all  these  roads  the  only  rocks  that 
were  seen  are  red  rocks  which  in  all  probability  belong  to  the  Pekin 
formation. 

The  next  line  across  the  field  on  which  traces  of  the  Cumnock 
formation  were  found  is  the  Carthage-Glendon  road.  As  far  north  as 
Cole’s  Mill  the  roads  both  to  the  south  and  the  west  of  the  main  road 
gave  no  indication  of  the  light-colored  rocks  of  the  Cumnock  formation ; 
in  fact,  there  seems  to  be  no  possibility  of  the  northeastward  extension 
of  the  belt  of  outcrop  of  the  Cumnock  formation,  showing  on  the 
Charlotte  road  northwest  of  Carthage,  for  the  road  from  Carthage  to 
Mooshaunee  and  also  the  road  from  Carthage  to  Cole’s  Mill  shows 
nothing  but  red  rocks  which,  unless  the  Cumnock  formation  changes 
in  color  in  this  locality,  cannot  belong  to  that  formation.  Likewise  the 


30 


THE  DEEP  KIVER  COAL  FIELD 


road  from  Cole’s  mill  to  Mooshaunee  is  on  red  rocks  from  one  of  these 
places  to  the  other. 

On  the  west  side  of  the  Glendon  road,  about  one  and  one-half  miles 
north  of  Cole’s  Mill,  the  Cumnock  formation  suddenly  appears  in 
full  force,  for  its  outcrop  extends  from  the  Carthage-Glendon  road 
for  fully  one-half  mile  to  the  west.  From  this  place  northward  the 
light-colored  rocks  were  seen  at  a number  of  places  as  also  were 
the  bands  of  black  shale  which  are  a characteristic  feature  of  the 
formation.  The  black  shale  is  particularly  well  exposed  and  prominent 
by  the  side  of  the  road  near  the  forks  where  the  road  to  the  Horseshoe 
bridge  turns  off  to  the  right  from  the  regular  Glendon  road.  The  Cum- 
nock formation  was  also  seen  on  all  the  roads  turning  to  the  northwest 
from  the  main  Carthage-Glendon  road  toward  Putnam  and  Cool 
Springs  Church.  On  the  main  Glendon  road  nearly  the  full  width  of 
lutcrop  was  seen  on  the  slope  northward  toward  McLennon’s  Creek, 
and  the  contact  between  the  light-colored  rocks  of  the  Cumnock  forma- 
tion and  the  red  beds,  which  are  supposedly  of  the  Pekin  formation, 
were  crossed  three-quarters  of  a mile  from  the  point  where  the  road 
forks  and  the  right  hand  fork  leads  to  Horseshoe  Bridge.  Between 
that  point  and  the  creek  and  also  on  the  northwest  side  of  the  creek 
for  some  distance  no  rocks  but  those  which  are  red  were  seen,  but  at 
a fork  of  the  road  about  one  mile  north  of  the  creek,  with  one  branch 
turning  to  the  left  toward  Cool  Springs  Church  and  the  other  turning 
off  the  main  road  to  the  right  toward  the  old  coal  mine  on  the  Jones 
property,  the  light-colored  rocks  of  the  Cumnock  formation  appear 
in  outcrop.  This  band  of  outcrop  is  only  900  feet  wide,  being  about 
one-third  of  the  normal  width  of  outcrop  of  the  entire  formation.  The 
dip  of  the  Cumnock  formation  could  not  he  determined  here  as  the 
rocks  are  soft  and  massive  and  no  bedding  planes  could  he  detected. 
Horth  of  this  narrow  band  of  outcrop  the  rocks  are  universally  red  as 
far  as  the  bridge  across  Deep  River  north  of  Glendon  where  the  red 
beds  of  the  Pekin  formation  rest  upon  the  crystalline  schist. 

The  two  bands  of  outcrop  of  the  Cumnock  formation,  mentioned 
above,  can  be  traced  northeastward  until  they  unite  two  miles  south- 
west of  Carbonton.  Thus  there  is  a main  hand  of  outcrop  of  the 
Cumnock  formation  from  a short  distance  north  of  Cole’s  Mill  north- 
eastward through  the  Horseshoe  Bend  of  Deep  River  and  on  to  Carbon- 
ton  which  appears  to  be  the  normal  outcrop  on  the  northwestern  limb 
of  the  Carthage  trough;  and  a second  band  of  outcrop  which  begins  in 
a sharp  point  one-half  mile  southwest  of  the  Carthage-Glendon  road, 
increases  in  width  to  900  feet  where  it  crosses  the  road  just  mentioned, 
and  gaining  the  full  width  of  outcrop  soon  after  it  crosses  Deep  River 


THE  DEEP  RIVER  COAL  FIELD 


31 


and  before  it  readies  the  village  of  Haw  Branch.  This  belt  of  outcrop 
continues  northeastward  to  the  vicinity  of  Carbonton  where  it  appears 
to  blend  with  or  unite  in  some  manner  with  the  other  band  of  outcrop 
lying  to  the  south. 

There  are  therefore  two  problems  here  that  call  for  an  explanation : 
(1)  The  failure  of  the  outcrop  of  the  Cumnock  formation  on  the 
Cartilage-Charlotte  road  to  connect  wTith  the  outcrop  of  the  same  forma- 
tion north  of  Cole’s  Mill,  and  (2)  the  bifurcation  of  the  outcrop  of 
the  Cumnock  formation  between  Carbonton  and  Haw  Branch. 

Several  explanations  might  be  offered  for  the  solution  of  problem 
Ho.  1,  but  each  one  is  open  to  some  objection  which,  in  the  light  of  the 
evidence  at  hand,  appears  to  be  fatal.  The  possible  explanations  that 
should  be  considered  by  any  geologist  working  in  this  field  in  the  future 
are  as  follows : 

(A)  That  the  outcrop  of  the  Cumnock  formation,  as  known  north 
of  Cole’s  Mill,  really  swings  to  the  west  and  connects  with  the  outcrop 
of  the  same  formation  on  the  Carthage-Charlotte  road  west  of  Rich- 
land Creek,  and  that,  owing  to  poor  exposures,  it  was  not  observed 
north  or  northwest  of  Mooshaunee. 

(B)  That  the  Carthage  trough  here  has  been  cut  by  a cross-fault 
and  the  part  south  of  the  fault  has  been  dropped  with  reference  to 
the  part  north  of  the  fault.  This  might  explain  the  offset  of  the 
Cumnock  formation,  but  it  is  difficult  to  conceive  of  such  a fault 
occurring  without  leaving  some  offset  in  the  line  of  contact  between 
the  Pekin  formation  and  the  underlying  schist. 

(C)  That  the  disappearance  of  the  typical  Cumnock  formation 
in  the  region  between  Cole’s  Mill  and  the  Carthage-Charlotte  road  is 
due  to  a local  change  in  sedimentation,  by  wffiich  the  generally  drab 
rocks  of  the  Cumnock  formation  are  displaced  by  red  sediments  similar 
to  both  the  overlying  and  the  underlying  formations  and  hence  are 
indistinguishable  from  them. 

(D)  That  there  is  here  an  overlap  of  the  red  rocks  of  the  Sanford 
formation  across  the  upturned  edges  of  the  rocks  of  the  Cumnock 
formation,  which  conceals  all  indications  of  the  presence  of  the  latter 
formation. 

(2)  The  question  of  the  bifurcation  of  the  outcrop  of  the  Cumnock 
formation  between  Carbonton  and  Haw  Branch  is  simpler,  but  of 
somewhat  greater  economic  importance,  because  it  affects  the  forma- 
tion where  it  possibly  contains  a workable  bed  of  coal.  Such  a bifurca- 
tion, as  that  shown  on  the  map,  could  have  occurred  in  only  one  of 
two  ways : being  the  result  of  either  a low  fold  or  wrinkle  on  the  side 
of  th<>  lqr£-e  though,  or  of  a normal  fault  which  has  dropped  the  block 


THE  DEEP  RIVER  COAL  FIELD 


STRUCTURE  PRODUCED  BY  FAULTING 


Carbonton 


Haw  Branch. 


Horseshoe  Bend  of  Deep  River 


Geologic  Structures 


THE  DEEP  EIVEB  COAL  FIELD 


33 


of  rock  on  the  northwest  side  or  raised  the  one  on  the  southeast  side, 
so  that  the  outcrop  of  the  Cumnock  formation  is  repeated  for  a distance 
of  about  three  and  one-half  miles.  The  fold  hypothesis  is  the  simpler 
one  and,  in  regions  in  which  the  rocks  are  subject  to  such  disturbances, 
it  would  be  accepted  without  much  question,  but  in  this  trough  folds  in 
the  rocks  are  almost  unknown  and  normal  faults  are  the  rule,  hence  in 
all  probability  the  bifurcation  of  the  outcrop  of  the  Cumnock  formation 
is  due  to  a fault  which  cuts  the  outcrop  at  a slight  angle,  as  shown 
in  Figure  2 and  described  more  fully  under  the  subject  of  Geologic 
Structure. 

The  trace  of  this  fault  follows  the  southern  margin  of  the  belt  of 
outcrop  that  passes  through  Haw  Branch  and,  if  it  extends  northeast- 
ward as  it  probably  does,  it  must  pass  somewhere  to  the  southeast  of 
Carbonton,  but  its  position  was  not  determined,  for  at  the  time  of  the 
field  examination  the  presence  of  this  fault  was  not  realized.  The 
wide  floodplain  of  Deep  River  about  Carbonton  makes  the  collection 
of  data  bearing  on  the  position  of  the  fault  difficult,  but  it  seems 
probable  that  if  search  were  made  in  the  vicinity  of  the  site  of  the  old 
village  some  evidence  of  the  inter-fingering  of  the  light-colored  rocks 
of  the  Cumnock  formation  and  the  red  rocks  of  the  Sanford  formation 
would  be  found.  The  representation  of  the  fault  on  the  map  as  well 
as  the  outcrop  of  the  formations  southeast  of  Carbonton  are  largely 
hypothetical,  but  they  serve  to  express  the  idea  that  the  writers  hold 
that  probably  there  is  at  this  place  a fault  which  separates  an  upraised 
block  of  the  earth’s  crust  on  the  southeast  from  a dropped  block  on  the 
northwest,  and  the  junction  of  the  two  belts  of  outcrop  of  the  Cumnock 
formation  in  the  vicinity  of  Carbonton  merely  means  that  here  the 
fault  passes  across  the  Cumnock  formation  and  farther  northeast  lies 
entirely  within  the  Sanford  formation,  or  at  least  is  in  this  position 
for  a number  of  miles.  On  this  assumption  the  belt  of  outcrop  of  the 
Cumnock  formation  which  extended  into  this  area  from  the  Horseshoe 
Bend  of  Deep  River  comes  to  an  end  in  a sharp  point  somewhere  in 
the  vicinity  of  Carbonton,  and  the  belt  lying  to  the  northwest  and 
passing  through  Haw  Branch  continues  on  to  the  northeast  through 
the  present  village  of  Carbonton  to  Gulf.  Ho  direct  measurement  of 
the  thickness  of  the  Cumnock  formation  was  made  in  the  vicinity  of 
Carbonton,  but  in  constructing  the  cross-sections  shown  in  Fig.  2 it 
was  found  that,  according  to  observed  dips  and  details  of  distribution 
of  outcrop,  the  formation  must  be  at  least  1,000  feet  thick. 

From  Carbonton  to  Gulf  the  base  of  the  Cumnock  formation  is 
quite  well  marked  on  the  ground  and  its  position  in  a number  of  places 
was  accurately  determined.  This  line  is  nearly  straight,  the  only 


Geol. — 3 


34 


THE  DEEP  RIVER  COAL  FIELD 


irregularities  being  those  due  to  the  influences  of  dikes  which  are  very 
abundant  and  seemingly  cut  the  coal  nearly  parallel  to  the  outcrop. 
The  upper  limit  of  the  formation  was  not  nearly  so  well  determined  as 
the  lower  limit,  for  it  follows  in  a general  way  the  floodplain  of  Deep 
Kiver,  and  this  floodplain  is  so  broad  that  it  was  not  thought  practical 
to  seek  for  evidence  regarding  the  exact  position  of  the  upper  limit 
of  the  formation. 

East  of  Gulf  the  writers,  when  in  the  field,  were  puzzled  by  the 
apparent  lack  of  parallelism  between  the  line  marking  the  lower  limit 
of  the  Cumnock  formation  and  the  line  marking  the  upper  limit.  Eh 
attempt  was  made  to  actually  follow  the  lower  boundary  of  the  forma- 
tion from  Gulf  to  the  Cumnock  bridge,  but  it  was  assumed  that  it  is 
regular  and  conformable  in  its  curve  and  direction  with  the  line  marking 
the  base  of  the  Pekin  formation  nearly  two  miles  to  the  north. 
Considerable  data  were  obtained  on  the  upper  boundary  of  the  Cumnock 
formation  and  it  was  found  not  to  be  conformable  with  the  line  marking 
the  base  of  the  Pekin  formation,  but  to  offset  decidedly  to  the  south 
at  a distance  of  about  a mile  from  Gulf.  A careful  study  of  the  com- 
piled map  shows  at  once  that  the  point  here  in  question  lies  almost  on 
the  continuation  of  the  supposed  Carbonton  fault  and  that  if  it  were 
granted  that  this  fault  might  continue  as  far  to  the  northeastward  as 
this  place,  it  would  account  for  the  irregularity  in  the  upper  boundary 
of  the  Cumnock  formation. 

All  of  the  facts  in  the  hands  of  the  writers  indicate  that  the  line 
marking  the  top  of  the  Cumnock  formation  crosses  Deep  Piver  about 
700  feet  below  the  bridge  at  the  old  mill  directly  south  of  Gulf.  This 
does  not  agree  with  the  statement  made  by  Chance  (pages  13-14)  that 
at  the  old  coal  mine  which  was  once  opened  west  of  the  village,  and 
which  was  abandoned  because  in  a short  distance  a large  dike  was 
encountered,  red  sandstone  appears  directly  south  of  this  great  dike.  It 
is  also  well  known  that  deep  drilling  was  done  here  years  ago,  but  no 
authentic  account  of  the  results  could  be  obtained;  there  is,  however, 
a vague  rumor  that  a well  near  the  river  bank  found  the  coal  at  a con- 
siderable depth  and  that  most  of  the  rocks  penetrated  near  the  surface 
are  the  red  rocks  of  the  overlying  formation.  If  these  rumors  are 
correct,  the  geology  about  Gulf  is  very  complicated  and  different  from 
that  which  is  represented  on  the  present  map,  but  the  writers,  while 
not  making  a special  examination  of  this  particular  locality,  have 
no  hesitation  in  saying  that  the  evidence  collected  in  the  surrounding 
territory  does  not  agree  with  such  an  interpretation  as  would  have 
to  he  made  if  the  rumor  mentioned  above  were  correct,  and  hence 
they  are  inclined  to  class  this  hearsay  evidence  as  too  vague  and  indefinite 


THE  DEEP  RIVER  COAL  FIELD 


35 


to  be  seriously  considered,  unless  it  were  substantiated  by  a detailed 
examination. 

As  stated  before,  the  writers  believe  that  tbe  line  marking  the  top 
of  tbe  Cumnock  formation  crosses  Deep  River  a short  distance  below 
tbe  bridge,  but  this  line  if  projected  to  tbe  east  would  not  include 
a great  mass  of  light-colored  sandstone  which  shows  still  farther  down 
the  river  and  at  an  old  quarry  about  half  way  between  the  river  and  the 
line  of  the  Southern  Railway,  about  a mile  southeast  of  Gulf.  As 
this  apparent  offset  in  the  upper  boundary  of  the  Cumnock  formation 
is  on  the  prolongation  of  the  Carbonton  fault,  it  is  suggested  that 
perhaps  this  fault  is  longer  than  has  been  supposed  and  really  is 
responsible  for  this  offset  as  well  as  the  much  larger  offset  of  the 
same  formation  southwest  of  Carbonton.  This  idea  of  the  extension 
of  the  fault  is  offered  more  in  the  nature  of  a suggestion  than  as  an 
established  fact  and  should  be  considered  by  any  coal  operator  who 
is  interested  in  the  development  of  this  part  of  the  field.  As  the 
evidence  in  the  vicinity  of  Haw  Branch  shows  that  the  fault  which 
is  supposed  to  be  responsible  for  the  offsets  in  the  Cumnock  formation 
is  diminishing  in  throw  or  magnitude  northeastward,  it  is  probable  that 
south  of  Gulf  it  may  not  have  lifted  the  coal  bed  more  than  100  feet 
and  it  probably  dies  out  before  it  reaches  the  schist  at  the  northern 
point  of  the  syncline.  As  the  movement  on  the  fault  plane  was  such 
as  to  cause  the  block  of  rock  on  the  southeast  side  of  the  fault  to  move 
upward  with  respect  to  the  block  on  the  northwest  side,  both  the  upper 
and  the  lower  boundary  of  the  Cumnock  formation  will  be  found  to 
offset  to  the  southwest,  but  for  only  about  1,500  feet  for  the  lower 
boundary  and  4,000  feet  for  the  upper  boundary,  the  difference  being 
caused  by  the  increasing  magnitude  of  the  fault  toward  the  southwest 
and  the  different  angle  at  which  the  fault  cuts  the  boundary  line. 

From  the  offset  just  described  to  Cumnock  and  the  Carolina  mine 
the  outcrop  of  the  Cumnock  formation  appears  to  be  exceedingly 
regular  and  without  offsets  of  any  kind.  It  is  possible,  however, 
that  if  it  could  be  followed  in  detail,  small  offsets  would  be  found 
for  some  small  faults  have  been  encountered  in  the  mines  which  would 
doubtless  produce  such  features  where  they  come  to  the  surface,  but 
they  are  so  small  that  it  would  be  almost  impossible  to  detect  them.- 

As  Offset  by  the  Deep  River  Fault. — East  of  Cumnock  and  the  Caro- 
lina mine  the  outcrop  of  the  Cumnock  formation  is  more  complicated 
than  it  is  at  any  other  point  seen  by  tbe  writers.  As  those  working  in 
the  coal  of  this  region  are  in  doubt  about  the  continuation  of  the  beds 
the  writers  spent  considerable  time  tracing  the  outcrop  between  the 
points  at  which  the  coal  has  been  prospected  in  the  vicinity  of  the 


36 


THE  DEEP  BIVEE  COAL  FIELD 


Carolina  mine  and  the  Capital  Highway  north  of  Sanford.  Professor 
Emmons,  in  his  report  of  1856,  gives  a colored  geologic  map  of  the 
Cumnock  formation  from  the  present  village  of  Carbonton  to  Cape 
Pear  River.  One  of  the  most  interesting  features  of  the  map  is  the 
great  bend  which  he  supposed  the  outcrop  of  the  formation  to  make 
just  east  of  Earmville  (now  the  Carolina  mine)  and  the  swing  to  the 
southwestward  across  the  river  some  distance  east  of  the  old  Endor  iron 
furnace  below  the  mouth  of  Buffalo  Creek.  The  outcrop  of  the  Cum- 
nock formation  is  represented  as  continuing  in  this  direction  to  beyond 
the  house  of  Evander  Mclver  where  it  turns  abruptly  to  the  southeast, 
paralleling  approximately  the  line  marking  the  contact  of  the  Pekin 
formation  and  the  underlying  crystalline  schist.  Emmons  gives  no 
facts  in  support  of  his  conception  of  the  great  bend  in  the  outcrop  of 
this  formation,  merely  stating  in  the  text  (p.  244)  that,  “The  outcrop 
crosses  the  river  between  Evander  Mclver’s  and  the  Hornville  property, 
thence  by  Farmville,  it  crosses  the  river  obliquely  at  Egypt,  and 
soon  recrosses  it  again  near  the  fish-trap,  and  passes  into  the  Taylor 
plantation.”  Haturally  the  writers  made  a very  detailed  examination 
of  this  part  of  the  field,  for  the  interpretation  of  the  Structure  neces- 
sarily has  an  important  bearing  upon  any  conclusion  regarding  the 
area  and  tonnage  of  available  coal. 

The  position  of  the  outcrop  of  the  Cumnock  coal  bed  from  Gulf 
to  the  Carolina  coal  mine  (Earmville  of  the  old  reports),  barring 
a hypothetical  offset,  is  quite  well  known  and  the  writers  were  able 
by  means  of  prospect  pits  to  continue  the  tracing  southeastward  beyoud 
the  Carolina  mine  to  the  edge  of  the  flood  plain,  about  1,300  feet 
from  Deep  River  at  the  bend  where  the  course  of  the  river  changes 
from  nearly  due  east  by  the  mouth  of  Pretty  Creek  to  a northward 
course  toward  Woodard’s  Bridge.  As  the  outcrop  of  the  coal  bed 
shows  no  trace  of  irregularity  save  a gentle  curve  toward  the  south, 
one  would  scarcely  expect  in  a distance  of  1,300  feet  a decided  change 
in  direction  of  the  outcrop  of  the  formation.  When,  however,  one 
tramps  from  Woodard’s  Bridge  up  the  river  bank  on  the  southeast 
side  he  finds  high  hills  of  schist  opposite  the  mouth  of  George’s  Creek 
and  even  further  south,  and  when  he  reaches  a point  in  strike  with 
the  outcrop  of  the  coal  at  the  last  prospect  pit,  he  finds  equally  high 
rugged  hills  made  of  a white  quartz  conglomerate,  in  all  respects 
similar  to  the  millstone  grit  exposed,  on  McCallum  Creek.  A<s  this 
conglomerate  strikes  H.  35°  E.  and  dips  15°  southeast,  it  will  be  seen 
at  once  that  it  is  out  of  harmony  with  the  coal  outcrop  and  also  with 
Emmons’  hypothesis  that  the  outcrop  of  the  coal  swings  abruptly  to 
the  southwest  across  Deep  River. 


THE  DEEP  RIVER  COAL  FIELD 


37 


In  order  to  test  Emmons’  hypothesis  still  further,  the  rocks,  showing 
on  the  south  side  of  the  river  from  the  mouth  of  Buffalo  Creek 
down  stream  to  the  bend  mentioned  above,  were  carefully  examined  as 
to  their  character  and  attitude,  but  nothing  was  found  that  would  in 
any  way  support  it.  The  rocks  throughout  this  stretch  of  river  are 
prevailingly  red  and  do  not  belong  to  the  Cumnock  formation.  The 
strike  of  the  rocks  from  the  mouth  of  Buffalo  Creek  to  the  mouth  of 
Pretty  Creek  are  parallel  with  the  outcrop  of  the  coal  bed  from  the 
Carolina  mine  to  the  river  flood  plain,  and  as  the  dip  is  to  the  south- 
west in  conformity  with  that  of  the  coal,  it  is  apparent  that  the  red 
sandstone  at  the  site  of  the  old  Endor  iron  furnace  overlies  the  coal  bed 
and  hence  belongs  to  the  Sanford  formation.  East  of  the  mouth  of 
Pretty  Creek  the  rocks  are  nearly  horizontal,  red  sandy  shale.  As 
these  in  all  probability  overlie  the  quartz  conglomerate  noted  above 
in  the  river  bluff,  a few  hundred  feet  to  the  north,  they  must  belong 
to  the  Pekin  formation. 

From  all  the  evidence  collected  in  the  field,  it  seems  certain  that 
the  Cumnock  formation,  including  the  workable  coal  bed  of  the  same 
name  comes  to  an  end  suddenly  near  the  last  coal  prospect  mentioned 
above.  The  reasons  for  this  conclusion  may  be  summarized  as  follows : 
(1)  If  the  coal  were  assumed  to  cross  the  river  on  its  regular  course 
it  would  strike  at  right  angles  the  basal  conglomerate  of  the  Pekin 
formation,  which  of  course,  without  the  intervention  of  a fault,  is 
impossible;  (2)  if  the  coal  bed  swings,  as  supposed  by  Emmons,  to  the 
southwest,  it  would  come  in  contact,  in  the  vicinity  of  the  site  of  the 
old  Endor  furnace,  at  right  angles  with  the  red  sandstone  of  the  Sanford 
formation.  As  each  of  these  assumptions  results  in  an  absurdity,  they 
cannot  be  regarded  seriously. 

The  only  theory  that  fits  the  known  facts  is  that  the  Cumnock 
formation,  including  the  coal  bed,  is  cut  by  a normal  fault  near  the 
first  coal  prospect  pit,  west  of  Deep  Biver.  The  movement  on  this  fault 
plane,  which  probably  is  nearly  vertical,  has  been  such  as  to  raise  the 
rocks  on  the  east  relative  to  those  on  the  west,  or  to  drop  those  on  the 
west  relative  to  those  on  the  east  about  2,500  feet  so  that  the  Cumnock 
coal  bed  comes  in  contact  on  this  fault  plane  with  the  base  of  the 
Pekin  formation  or  with  the  underlying  schist  on  the  east  side  of 
the  fault.  The  fault  swings  somewhat  to  the  southwest  and  crosses 
Deep  Kiver  at  or  near  the  mouth  of  Pretty  Creek.  The  real  test  of 
the  fault-hypothesis  is  whether  or  not  boundaries  other  than  those 
of  the  Cumnock  formation  are  offset  in  a similar  manner  and  to  a 
like  amount. 


38 


THE  DEEP  RIVER  COAL  FIELD 


The  first  boundary  line  to  be  tested  is  that  marking  the  base  of 
the  Pekin  formation  or  the  contact  between  that  formation  and  the 
underlying  schist.  This  boundary  was  located  on  the  road  running 
nearly  north  from  the  bridge  across  Deep  River  at  Cumnock,  as 
shown  on  the  accompanying  map.  It  was  also  determined  on  the  road 
from  west  of  the  Carolina  coal  mine  to  the  Sanford-Pittsboro  road. 
This  also  is  shown  on  the  map.  The  base  of  the  Pekin  formation  as 
represented  by  these  points  is  roughly  parallel  to  the  outcrop  of  the 
coal  bed  and  at  the  last  mentioned  place  the  boundary  swings  to  the 
southeast  in  almost  exact  conformity  to  that  of  the  coal  bed.  As  the 
outcrop  of  the  coal  bed  could  not  be  followed  to  the  supposed  fault- 
line, it  was  essential  to  trace  the  contact  of  the  Pekin  formation 
and  the  schist  southeastward  from  this  road  as  far  as  it  extends.  This 
line  was  crossed  almost  due  south  of  the  point  where  the  road  from 
the  Carolina  mine  intersects  the  Pittsboro  road.  When  platted  this 
point  proved  to  be  on  the  extension  of  the  contact  line  from  the  west 
and  afforded  no  indication  of  being  near  the  end  of  the  Pekin  formation. 
Again  the  contact  was  crossed  near  Deep  River  where  the  stream  turns 
from  due  north  to  almost  east,  a course  that  it  follows  to  Woodard’s 
Bridge.  Here  at  a point  800  feet  north  of  the  river  the  contact  was 
again  found,  or  at  least  fragments  of  a quartz  conglomerate,  which 
undoubtedly  is  the  basal  conglomerate  of  the  Pekin  formation,  were 
found  on  schist.  Horth  of  this  point  nothing  but  schist  fragments 
appear  on  the  surface  and  south  of  the  point  nothing  was  seen  on  the 
surface  but  fragments  of  conglomerate  and  brown  sandstone.  It  was 
found  that  this  point  is  in  line  with  the  other  points  to  the  west  in 
indicating  a gently  southward  curving  boundary  line  similar  to  that 
marking  the  outcrop  of  the  coal  bed.  West  of  this  point  all  indications 
point  to  perfectly  normal  relationships,  but  east  of  the  point  there 
was  nothing  to  be  found  but  schist  and  it  Avas  found  that  this  schist 
extends  south  to  the  river  where  it  shows  as  a ledge  projecting  into 
the  north  side  of  the  stream.  Here,  as  further  north,  brown  sand- 
stone fragments  are  abundant  to  the  west  of  the  schist  so  that  it  is 
concluded,  and  seemingly  without  the  possibility  of  error,  that  this 
line  of  contact  between  fragments  of  sandstone  and  conglomerate  on 
the  west  and  schist  on  the  east  marks  the  line  of  the  fault. 

Prom  the  point  described  above  southward  (up  stream)  all  the 
rocks  exposed  on  the  Avest  side  of  the  river  belong  to  the  Hewark 
group,  but  all  those  on  the  east,  as  determined  by  a foot-traverse 
along  the  river  bank,  are  schist  up  to  the  next  great  bend  in  the  course 
of  the  river  where  it  turns  from  an  easterly  to  a northerly  course. 
As  the  rocks  on  the  west  are  Hewark  and  on  the  east  schist  it  is 
obvious  that  the  fault  folloAvs  closely  the  flood  plain  of  the  river  and 


THE  DEEP  KIVER  COAL  FIELD 


39 


consequently  its  exact  position  cannot  be  determined.  Where  the 
fault  crosses  the  river  east  of  the  mouth  of  Pretty  Creek  it  is  in 
the  midst  of  red  rocks  and  here  its  position  can  only  he  inferred. 

As  shown  on  the  map,  the  line  marking  the  base  of  the  Pekin 
formation  is  offset  to  the  south  by  this  fault  one  and  one-half  miles. 
It  seemed  probable,  therefore,  that  the  coal  outcrop  would  be  found 
on  the  east  side  of  the  fault  about  one  and  one-half  miles  to  the  south 
of  the  last  pit  noted  southeast  of  the  Carolina  mine. 

Professor  Emmons  in  his  report  of  1856  mentions  the  occurrence 
of  coal  near  the  house  of  Evander  Mclver  and  at  Martin  Dyer’s, 
although  he  does  not  give  the  thickness  of  the  coal  bed  at  either  place, 
except  to  say  that  a boring  at  Martin  Dyer’s  disclosed  10  inches  of 
coal.  The  Martin  Dyer  farm  is  on  the  main  Capital  Highway  two  and 
one-half  miles  from  Sanford  and  about  one-quarter  of  a mile  south 
of  the  “Old  Cumnock”  road.  Evander  Mclver  lived  on  this  road  a 
little  more  than  two  miles  from  the  Capital  Highway  and  about  three- 
quarters  of  a mile  from  the  crossing  of  the  Southern  Railway. 

According  to  local  reports  the  coal  was  mined  quite  extensively 
during  the  Civil  War  in  Pretty  Creek  north  of  the  Mclver  house. 
These  old  mines  were  located  by  the  writers  and  the  belt  of  light- 
colored  Cumnock  rocks  was  followed,  as  indicated  on  the  map,  south- 
eastward to  the  Capital  Highway.  In  the  opposite  direction  the  rocks 
are  poorly  exposed,  but  light-colored  shale  associated  with  fine  fissile 
black  shale  was  found  in  a cut  on  the  Southern  Railway  nearly  a 
mile  south  of  the  crossing  of  the  “Old  Cumnock”  road.  As  cuts  on 
the  railroad  just  south  of  this  crossing  are  in  thick-bedded  red  sand- 
stone, it  seems  probable  that  the  outcrop  of  the  Cumnock  formation 
trends  nearly  due  west  from  the  Mclver  house  to  the  valley  of  Buffalo 
Creek.  As  all  of  the  rocks  in  the  upland  west  of  this  creek  are  red, 
the  belt  of  Cumnock  formation  must  be  cut  off  suddenly  somewhere 
in  the  valley  of  Buffalo  Creek  by  a fault  which  brings  the  Cumnock 
formation  on  the  east  side  in  contact  with  red  sandstone  and  shale  of 
the  Sanford  formation  on  the  west.  In  other  words,  this  is  the  same 
fault  as  that  which  was  discovered  north  of  Deep  River,  and  the  offset 
of  the  principal  coal  bed  is  about  one  and  one-half  miles,  or  the  same 
as  the  offset  of  the  base  of  the  Pekin  formation. 

The  evidence  in  this  part  of  the  field  is  perfectly  clear  that  the 
geographic  distribution  of  the  Cumnock  formation,  as  noted  by  Professor 
Emmons  and  as  found  by  the  writers,  is  the  result  of  a normal  or 
nearly  vertical  fault  or  break  in  the  rocks  which  has  affected  not 
only  the  sandstone,  shale,  and  conglomerate  of  the  Newark  group,  but 
also  the  underlying  crystalline  schist.  It  is  impossible  on  account  of 


40 


THE  DEEP  KIVEE  COAL  FIELD 


the  similarity  of  the  schist  on  the  two  sides  of  the  fault,  to  trace 
the  fault  far  beyond  the  outer  boundary  of  the  Pekin  formation  and  in 
the  other  direction  it  is  equally  difficult  to  trace  it  far  into  the  interior 
of  the  Carthage  trough,  because  here  it  is  entirely  within  the  Sanford 
formation  and  the  red  sandstone,  shale  and  conglomerate  in  one  part 
of  this  formation  are  so  like  those  in  another  part  that  they  are 
indistinguishable. 

On  the  map  the  fault  is  shown  for  only  a few  miles  south  of  the 
Evander  Mclver  house,  but  with  a displacement  at  the  river  of  at 
least  2,500  feet,  it  seems  probable  that  it  extends  much  further,  possibly 
as  far  as  to  the  vicinity  of  Carthage. 

East  of  the  Deep  River  fault  the  tracing  of  the  outcrop  of  the 
Cumnock  formation  is  extremely  unsatisfactory  because  of  the  blanket 
of  quartz  pebbles  on  the  higher  land,  the  heavy  forest  which  prevails 
over  most  of  the  country  in  this  region,  and  the  probable  complicated 
structure  which  seemingly  has  resulted  in  the  dislocation  of  the  band 
of  outcrop  into  a number  of  isolated  areas. 

The  first  of  these  isolated  areas  of  the  Cumnock  formation  extends 
southeastward  from  the  Deep  River  fault  to  something  more  than 
a mile  east  of  the  Sanford-Colon  Highway.  The  coal  beds  in  this  forma- 
tion have  been  prospected  in  the  valley  of  the  upper  part  of  Pretty 
Creek  just  north  of  the  “Old  Cumnock”  road.  The  outcrop  of  the 
formation  follows  this  road  from  a short  distance  east  of  the  Atlantic 
and  Yadkin  (Southern)  Railway  to  the  Capital  Highway,  two  and 
three-fourths  miles  north  of  Sanford.  The  light-colored  rocks  of  the 
formation  are  well  exposed  in  a cut  on  the  Seaboard  Air  Line  Railway 
about  the  same  distance  from  Sanford  where  they  strike  N.  60°  E. 
and  dip  30°  to  the  southeast.  Fragments  of  the  light-colored  rocks 
marking  the  southern  boundary  of  the  Cumnock  formation  may  be 
seen  on  the  road  from  Sanford  to  Colon  at  a distance  of  one  and  three- 
fourths  miles  from  the  main  street  leading  nearly  due  east  from 
the  center  of  Sanford.  From  the  last  mentioned  place  the  outcrop  of 
light  buff  sandstone  was  traced  continuously  nearly  due  east  through 
the  forest  for  a distance  of  one  and  one-half  miles  to  the  zone  of  dikes 
which  passes  a little  north  of  west  through  the  village  of  Colon  on 
the  Seaboard  Air  Line  and  the  Norfolk  Southern  railroads. 

East  of  the  Sanford-Colon  Highway  the  belt  of  light-colored  rocks 
appears  to  grow  narrower  and  narrower  towards  the  east  until  it 
disappears  as  stated  above,  in  the  zone  of  dikes.  It  is  probable  that 
other  bands  of  light-colored  rocks  may  extend  into  this  forest-covered 
region,  but,  if  so,  they  are  separated  by  red  conglomerate  which  probably 
interfingers  with  the  light-colored  sandstone  and  shale.  The  writers 


THE  DEEP  RIVEE  COAL  FIELD 


41 


are  strongly  of  the  opinion  that,  as  the  southeastern  margin  of  the 
trough  is  approached,  the  Cumnock  formation  is  split  up  by  layers  of 
red  rocks  which  increase  in  number  and  thickness  until  possibly 
the  light-colored  rocks  of  the  formation  are  entirely  replaced  by  red 
sandstone,  shale,  and  conglomerate  that  cannot  be  differentiated  from 
the  overlying  and  underlying  rocks.  If  the  northeastward  termination 
of  the  Carthage  trough  as  explained  later  under  the  heading  “Geologic 
Structure,”  is  due  to  the  formation  of  a cross-anticline  in  the  vicinity 
of  Colon,  then  the  outcrop  of  the  Cumnock  formation  should,  if  it 
were  unbroken,  extend  in  general  eastward  south  of  Colon  until  it 
reaches  the  axis  of  the  cross-anticline  and  then  it  should  loop  back  to 
the  northwest  in  a line  nearly  parallel  with,  but  departing  more  and 
more  to  the  northward  from  the  outcrop  already  described,  until  it 
reaches  the  point  where  it  turns  northeastward  along  the  rim  of  the 
Corinth  trough. 

The  writers  examined  this  part  of  the  field  with  considerable  care 
in  order  to  determine  whether  or  not  the  outcrop  does  swing  back  on 
the  north  side  of  the  Colon  anticline,  but  no  trace  of  it  could  be 
found.  As  the  outcrop  extends  only  as  far  east  as  the  dikes  mentioned 
before  it  seems  probable  that  the  formation  is  cut  off  by  a fault 
which  follows  the  course  of  the  dikes  and  possibly  passes  through 
and  is  responsible  for  the  sharp  angle  in  the  line  marking  the  base 
of  the  Pekin  formation  near  the  Capital  Highway  and  the  Horfolk 
Southern  Railroad.  The  reason  for  this  supposition  will  be  more 
fully  considered  under  the  heading  “Geologic  Structure.” 

In  the  Corinth  Trough. — From  Colon  northeastward  to  Zion  Church 
a careful  examination  was  made  for  any  drab  shale  or  light-colored 
sandstone  that  might  indicate  the  presence  of  the  Cumnock  formation^ 
but  none  was  found.  In  most  cases  the  outcrops  are  so  poor  that  one 
cannot  be  certain  that  light-colored  rocks  are  not  present,  but  one 
section  was  found  that  shows  almost  continuous  exposures  of  red 
rocks  from  near  the  Capital  Highway  on  the  northwest  to  the  Osgood- 
Zion  Church  road  on  the  southeast.  This  section  is  on  a road  which 
leaves  the  Capital  Highway  at  Jones  Chapel  and  intersects  the  Osgood- 
Zion  Church  road  about  a mile  north  of  Osgood  and  the  rocks  dip 
continuously  to  the  southeast  throughout  practically  the  whole  of  this 
section.  Here  apparently  is  a line  across  which  the  outcrop  of  the 
Cumnock  formation  does  not  pass,  unless  its  rocks  are  different  from 
those  which  are  generally  recognized  as  typical. 

Although  the  Cumnock  formation  is  absent  in  the  section  just 
mentioned,  it  comes  in  suddenly,  and  with  its  characteristic  light  drab 
color,  only  a mile  or  so  to  the  northeast,  as  shown  by  a coal  prospect 


42 


THE  DEEP  BIVEE  COAL  FIELD 


and  associated  light-colored  rocks  in  the  proper  position  to  be  in  the 
Cumnock  formation.  One-balf  mile  north  of  Zion  Church  a thin  layer 
of  coal,  only  a few  inches  thick  has  been  exposed  in  a pit  dug  on  the 
farm  of  Morris  Holt.  Here  adjacent  bands  of  gray  sandstone  lying 
both  above  and  below  the  coal  bed  and  also  the  debris  of  light-colored 
sandy  shale  that  cumbers  the  hillsides  in  the  vicinity,  all  point  to  the 
fact  that  a belt  of  light-colored  rocks  strikes  parallel  with  the  boundary 
of  the  field  and  dips  normally  to  the  southeast  at  an  angle  of  25  degrees. 
The  width  of  this  belt  of  outcrop  was  not  determined,  but  where  the 
belt  is  crossed  by  a small  stream  near  the  coal  pit,  the  light-colored 
rocks  were  seen  for  a distance  of  several  hundred  feet  on  either  side 
of  the  pit. 

The  coal  prospect  noted  above  on  the  Holt  farm,  appears  to  be 
the  same  as  that  mentioned  by  Professor  Emmons  in  his  report  of 
1856  (p.  244)  as  occurred  on  the  Rhiney  Wicker  (Ellington)  property. 
He  notes  that  the  coal  bed  here  is  less  than  three  inches  thick,  and 
this  agrees  exactly  with  the  statement  of  Morris  Holt,  who  a few  years 
ago  sunk  a pit  to  the  coal  bed.  Professor  Emmons,  however,  does  not 
regard  this  belt  of  coal-bearing  rocks  as  occurring  in  the  Cumnock 
formation,  but  thinks  that  it  is  associated  with  the  upper  red  sand- 
stones and  conglomerates  (Sanford  formation)  and  not  the  same  as  the 
rocks  exposed  in  the  Cumnock  shaft.  His  conclusions  were  based  on  the 
proximity  of  a fossil  plant-bearing  shale  to  the  coal  and  sandstone. 
It  is  true  that,  although  the  succession  of  strata  from  the  schist  upward 
is  practically  the  same  as  it  is  at  Cumnock,  the  thickness  of  the 
Pekin  and  the  Cumnock  formations  is  very  much  less.  The  data  at  hand 
do  not  permit  of  an  accurate  measurement  of  these  formations  at  the 
Morris  Holt  farm,  but  the  Pekin  formation  is  probably  about  1,000 
feet  and  the  Cumnock  formation  not  more  than  800  feet  thick  at  this 
place.  The  present  writers  have  carefully  considered  all  of  these 
points,  and,  though  they  regard  Professor  Emmons’  conclusions  as 
possible,  the  succession  of  beds  strongly  suggests  that  the  formations 
are  the  same  as  those  that  have  been  observed  farther  west. 

Although  the  writers  believe  that  the  coal  on  the  Morris  Holt  farm 
is  in  the  Cumnock  formation  they  must  admit  their  inability  to 
explain  the  disappearance  of  this  formation  in  the  district  about 
Colon.  Here  then  is  a case  of  disappearance  of  the  Cumnock  formation, 
very  similar  to  the  disappearance  of  the  same  rocks  in  the  vicinity 
of  Mooshaunee  which  was  described  on  another  page.  The  only 
difference  in  the  two  cases  is  that  south  of  Colon  there  is  positive 
evidence  that  the  formation  changes  in  character  by  the  occurrence 
in  it  of  beds  of  red  conglomerate  which  cannot  be  distinguished  from 


THE  DEEP  RIVER  COAL  FIELD 


43 


the  red  conglomerate  of  the  Sanford  formation,  and  it  is  possible  that, 
if  the  outcrop  of  the  formation  could  be  followed  to  the  southwest 
from  the  Morris  Holt  farm,  it  likewise  would  be  found  to  split  and 
become  red  by  the  introduction  of  red  conglomerate  between  the  layers 
of  drab  or  gray  sandstone  and  shale. 

From  the  farm  of  Morris  Holt  the  outcrop  of  the  Cumnock  forma- 
tion probably  extends  continuously  northeastward  beyond  the  limit 
of  the  territory  represented  by  the  map  accompanying  this  report,  but 
it  is  not  well  shown  at  any  point  visited  by  the  writers.  Light-colored 
rocks  were  seen  on  the  southwest  side  of  Deep  River  on  the  road  from 
Osgood  to  Lockville  and  on  the  northeast  side  of  Deep  River  in  the 
vicinity  of  Moncure.  Various  rumors  were  heard  in  the  village  of 
Moncure  about  coal  having  been  struck  in  bored  wells  in  the  village 
and  also  in  pits  sunk  for  the  foundations  of  the  water  tank  near  the 
railroad  station,  but  the  accuracy  of  these  reports  is  subject  to  question. 
In  drilling  a water-well  in  the  village  the  drill  is  said  to  have  passed 
through  a few  inches  of  black  material  which  may  have  been  coal  or 
black  shale.  The  report  that  coal  was  exposed  when  the  foundations 
of  the  water  tank  were  laid  could  not  be  confirmed  by  the  records  in 
the  office  of  the  Chief  Engineer  of  the  Seaboard  Air  Line  Railway ; 
therefore  the  writers  conclude  that  the  evidence  regarding  the  presence 
of  coal  at  Moncure  is  of  very  doubtful  value  and  at  best  does  not 
seem  to  indicate  a thickness  of  more  than  a very  few  inches. 

Sanford  Formation 

The  rocks  above  the  Cumnock  formation  are  almost  universally  red, 
being  composed  largely  of  conglomerate,  sandstone  and  shale  in  a 
monotonous  succession,  which  crops  out  across  the  trough  from  the  upper 
limit  of  the  Cumnock  formation  to  the  Jonesboro  fault.  As  these  red 
beds  are  present  under  and  around  the  town  of  Sanford  that  name  is 
proposed  for  the  formation  which  includes  all  rocks  of  Triassic  age 
above  the  Cumnock  formation. 

The  Sanford  formation  has  little  of  interest  to  one  seeking  for  coal, 
for,  so  far  as  known,  there  are  no  coal  beds  in  it,  and,  in  fact,  very 
little  except  red  rocks.  These  consist  of  red  conglomerate,  which 
apparently  varies  in  coarseness  according  to  its  nearness  to  the  south- 
eastern border  of  the  field,  for  from  this  direction  came  most,  if 
not  all,  of  the  materials  composing  it.  The  pebbles,  cobbles,  and 
boulders  found  in  the  formation  were  largely  derived  from  the  crystalline 
schist  and  slate  (PL  IV-A),  but  the  largest  boulders  observed  are  of 
granite  (PL  IV-B),  a large  mass  of  which  apparently  was  intruded 
into  the  schist  just  east  of  the  present  boundary  of  the  Hewark  rocks 
on  the  east  side  of  Cape  Fear  River. 


44 


THE  DEEP  KIVEK  COAL  FIELD 


The  cuts  made  in  grading  for  the  Norfolk  Southern  Railroad  between 
Colon  and  Corinth  offer  the  best  field  for  a study  of  the  characteristics 
of  the  Sanford  formation.  In  the  cuts  directly  east  of  Colon  the 
material  is  relatively  fine,  few  of  the  individual  cobbles  being  more 
than  six  inches  in  diameter,  but  near  Corinth  the  material  is  much 
coarser,  one  boulder  of  granite  (PI.  IY-B)  near  the  Jonesboro  fault 
measuring  four  feet  in  its  longer  diameter.  A few  hundred  yards 
beyond  the  point  where  this  boulder  is  exposed  in  the  railroad  cut  the 
Sanford  formation  rests  directly  against  a mass  of  granite  from  which 
the  boulder  doubtless  was  derived. 

The  thickness  of  the  Sanford  formation  is  evidently  very  great, 
but  no  geologist  so  far  has  secured  sufficient  data  to  make  a very 
reliable  estimate.  In  1852  Professor  Emmons,  in  discussing  this  matter, 
arrived  at  the  conclusion  (p.  137)  that  the  thickness  of  the  upper  red 
sandstones  (Sanford  formation)  is  3,000  feet,  but  confessed  that  his 
estimate  was  vague  and  of  little  value,  except  as  a minimum  measure, 
which  he  thought  might  be  very  materially  increased,  if  adequate  data 
were  available.  At  the  present  time  the  outline  of  the  field  is  much 
better  known  than  it  was  in  1852  and  it  is  possible  to  make  a better 
estimate,  but  even  today  there  are  many  unknown  or  variable  factors 
in  the  problem  which  render  the  result  only  approximately  correct. 

In  making  an  estimate  of  the  total  thickness  of  rocks  in  the  Deep 
River  Coal  Field,  it  is  evident  that  the  field  is  naturally  divisible  into 
two  parts;  the  line  of  separation  being  in  the  vicinity  of  Colon, 
three  miles  northeast  of  Sanford.  The  trough  southwest  of  Colon  is 
broader  and  seemingly  shallower  than  the  trough  to  the  northeast 
of  that  place,  hence  it  seems  probable  that  a greater  thickness  of 
rocks  is  involved  in  the  latter  than  in  the  former  trough.  Although 
the  trough  southwest  of  Colon  is  shallower,  it  is  more  irregular  in 
structure  and  is  not  well  adapted  to  a measurement  of  thicknesses, 
particularly  when  it  is  remembered  that  all  its  eastern  part  is  largely 
obscured  by  white  sand  which  mantles  the  hard  rocks  and  almost 
completely  conceals  them.  For  this  reason  the  southwestern  trough 
has  been  disregarded.  The  trough  northeast  of  Colon  is  narrower,  but 
the  dips  are  much  more  constant  across  it  from  one  margin  to  the 
other;  consequently  it  offers  decidedly  better  opportunities  to  obtain 
a reasonably  accurate  estimate  of  the  thickness  of  rocks  involved,  unless 
it  is  cut  by  longitudinal  faults  which  duplicate  the  measures.  The 
best  estimate  that  can  be  made  at  the  present  time  is  that  the  Sanford 
formation  is  probably  4,000  or  5,000  feet  thick.  If  this  thickness  is 
correct  then  the  entire  Newark  group  has  a probable  thickness  of 
7,000  to  8,000  feet  and  the  crystalline  schist  lies  at  approximately  that 


PLATE  IV 


A.  Boulders  of  schist  in  the  Sanford  formation.  View  in  cut  of  the  Norfolk 
Southern  Railroad  east  of  Corinth.  The  boulders  are  badly  decayed,  but  range 
in  diameter  up  to  16  inches. 


B Boulder  of  granite  in  the  Sanford  formation.  This  boulder,  i feet  in  diameter, 
shows  in  a cut  of  the  Norfolk  Southern  Railroad  nearly  three  miles  east  of 
Corinth. 


THE  DEEP  BIVEB  COAL  FIELD 


45 


depth,  below  the  surface  in  the  vicinity  of  Corinth  on  the  Norfolk 
Southern  Railroad,  east  of  Cape  Fear  River. 

Igneous  Dikes 

The  rocks  of  the  Newark  group,  as  well  as  the  underlying  crystalline 
schist  in  the  Deep  River  Field  are  cut  by  numerous  dikes  of  diabase, 
but  their  outcrops  are  so  greatly  obscured  by  sand,  gravel  and  the 
forest  that  the  writers  made  little  effort  to  map  them  in  detail; 
they  were,  however,  carefully  noted  wherever  they  crossed  the  highways 
and  other  lines  of  travel  where  their  outcrops  are  plainly  visible.  An 
effort  was  made  in  a small  area  northwest  of  Sanford  to  trace  and 
map  several  dikes  off  the  highways,  but  after  one  day’s  experience  in 
tracing  the  dikes  through  cultivated  fields,  woodlands  and  swamps,  it 
ivas  given  up  as  impracticable. 

The  dikes,  although  somewhat  irregular  in  their  trend,  seem  to  belong 
to  a great  system  which  in  general  trends  N.  20  degrees  W.  They 
are  probably  fairly  evenly  distributed  throughout  the  territory,  although 
they  are  not  so  represented  on  the  map.  This  seeming  irregularity  in 
occurrence  is  due  in  part  to  the  greater  number  of  routes  traversed  in 
certain  parts  of  the  field  than  in  others,  and  in  part  to  the  better 
exposures  near  the  river  and  the  larger  creeks  than  there  are  on  the 
upland,  where  the  blanket  of  sand  and  gravel  is  unusually  thick. 
Although  the  dikes  are  present  in  almost  every  part  of  the  field,  close 
examination  shows  that  in  certain  places  they  are  much  more  numerous 
than  they  are  in  others,  and  in  certain  large  areas  they  seem  to  be 
absent.  When  one  makes  an  examination  of  the  outcrop  of  the  Cumnock 
formation  from  Haw  Branch  to  Gulf,  he  is  impressed  with  the  frequency 
with  which  he  encounters  dikes  or  the  boulders  resulting  from  the  decay 
of  dikes.  They  seem  to  follow  the  outcrop  of  the  coal  beds,  for  they 
are  present  at  almost  every  prospect  that  has  been  opened  for  coal  in 
this  part  of  the  trough.  The  parallelism  of  the  dikes  and  the  coal 
outcrops  is  certainly  true  for  a distance  of  a mile  or  two  in  the  vicinity 
of  Carbonton,  but  north  of  Indian  Creek  there  does  not  appear  to  be 
such  a close  agreement  in  direction  as  there  is  south  of  that  creek.  The 
prevalence  of  dikes  on  the  outcrop  of  the  coal  beds  about  Carbonton  has 
had  a decidedly  detrimental  effect  on  the  commercial  development  of  the 
coal.  When  one  compares  the  general  absence  of  dikes  on  the  ridge 
which  the  Sanford-Cumnock  road  follows  for  three  or  four  miles 
south  of  Cumnock,  with  their  abundance  about  Carbonton,  he  is 
decidedly  impressed  with  the  irregularity  rather  than  the  regularity 
of  their  occurrence. 

The  composition  of  the  dikes,  as  shown  by  a sample  collected  near 
the  point  where  the  Carthage-Charlotte  Highway  crosses  Richland 


46 


THE  DEEP  RIVER  COAL  FIELD 


Creek  and  another  from  a cut  of  the  Norfolk  Southern  Railroad  a short 
distance  southwest  of  Gulf,  is  that  of  a typical  diabase  with  only  a very 
little  magnetite.  This  seems  strange,  as  the  dikes  had  such  a disastrous 
effect  on  the  magnetic  needle  during  the  present  survey,  but  it  is  probable 
that  the  magnetic  attraction  is  due  to  the  polarization  of  the  dike 
material  rather  than  to  the  composition  of  the  rock. 

In  general  the  dikes  cut  the  country  rock  in  an  almost  vertical 
direction,  and  in  most  cases  where  their  bounding  walls  can  he  seen 
they  are  extremely  regular  and  the  thickness  of  the  dike  varies  hut 
little.  In  some  railroad  cuts  where  the  dikes  are  visible  for  ten  to 
twenty  feet  it  was  found  that  they  are  approximately  vertical,  that 
they  frequently  cut  through  the  bedded  rocks  without  causing  any 
deformation,  hut  here  and  there  the  sandstone  beds  on  one  or  the 
other  side  of  the  dike  are  pushed  up  out  of  their  normal  position  as 
much  as  twenty  degrees,  showing  that  the  igneous  material  was  forced 
up  under  great  pressure  and  that  in  places  it  lifted  the  country  rock 
out  of  its  normal  attitude.  One  of  the  best  examples  of  tilting  caused 
by  a dike  was  seen  in  a deep  cut  of  the  Norfolk  Southern  Railroad  on 
the  southwest  bank  of  Cape  Fear  River  in  the  eastern  part  of  the 
field.  The  photograph  of  this  dike  is  reproduced  as  PI.  Y-B.  As 
shown  by  the  plate,  the  dike  stands  about  vertical,  but  the  sandstone 
on  the  left  which  normally  outcrops  in  a nearly  horizontal  line  is 
tilted  or  lifted  up  about  twenty-five  degrees.  The  beds  on  the  right  are 
not  clearly  shown  in  the  cut,  but  at  the  time  the  picture  was  taken, 
they  were  studied  with  some  care  and  no  sign  of  a corresponding  dip 
was  detected. 

Although  the  dikes  generally  have  regular  and  parallel  bounding 
walls,  there  are  apparently  some  exceptions  to  this  rule.  The  most 
notable  case  that  was  seen  is  a dike  cutting  the  Cumnock  formation 
at  the  north  end  of  the  dam  of  the  Sand  Hill  Power  Company  at 
Carbonton.  A part  of  this  dike  is  shown  in  PI.  YI-B.  The  exposure 
occurs  at  the  end  of  the  dam  shown  in  PI.  YI-A;  in  fact  the  camera 
was  resting  on  the  dike  when  the  picture  of  the  dam  was  taken.  On 
PI.  VI-B  the  left  edge  of  the  dike  is  indicated  by  the  camera  case  and 
the  hammers.  At  this  point  it  comes  in  contact  with  the  cut  edges  of 
the  dark  indurated  shale  of  the  Cumnock  formation  which  here  dips 
to  the  northwest  or  away  from  the  observer  about  ten  degrees.  The 
contact  of  the  dike  and  the  shale  rises  and  curves  to  the  right  until  it 
reaches  the  main  mass  of  the  dike  perhaps  eight  or  ten  feet  to  the  right 
of  the  rock  showing  in  PI.  VI-B.  This  contact  is  sharp  and  irregular 
showing  that  the  shale  has  been  broken  away  by  blocks  and  there  is 


THE  DEEP  EIVEB  COAL  FIELD 


47 


no  suggestion  of  the  country  rock  having  been  fused  by  the  heat  of  the 
molten  mass  of  the  dike.  This  is  one  of  the  best  exposures  of  the  walls 
of  a dike  that  was  seen. 

The  dikes  range  in  thickness  from  a few  inches  to  about  100  feet, 
and  it  is  not  thought  that  any  dike  in  this  field  has  a greater  thickness 
than  that  just  given.  Some  very  minute  dikes  were  observed  in  a 
homogeneous  red  sandstone  by  the  roadside  just  west  of  McLennon’s 
Creek  on  the  road  leading  from  Carthage  to  Mooshaunee.  Some  of 
these  dikelets  are  no  thicker  than  a knife  blade  and  none  exceeds  a 
quarter  of  an  inch  in  thickness.  They  radiate  in  all  directions,  follow- 
ing a system  of  minute  fissures  that  doubtless  was  developed  in  the 
sandstone  before  the  intrusion  occurred.  These  dikelets  are  shown 
on  PI.  Y-A. 

It  is  interesting  to  note  that  the  dikes  have  a very  decided  effect 
on  the  circulation  of  underground  water  and  that  this  fact  is  utilized 
in  the  field.  Thus  the  inhabitants  have  learned,  through  long  experi- 
ence, that  water  can  be  secured  much  more  readily  by  sinking  wells 
near  a dike  than  it  can  in  the  country  rock  where  there  is  no  dike. 
From  this  fact  it  is  evident  that  the  dike  serves  as  a barrier  to  the 
circulation  of  liquids  through  the  rocks  and  that  next  to  the  barrier 
a pool  is  formed.  If  there  were  any  petroleum  in  the  rocks  it  is 
probable  that  it  would  be  affected  in  a similar  manner  and  consequently 
any  test  wells  that  are  put  down  should  he  drilled  near  the  dikes  or  at 
least  so  they  would  strike  the  porous  reservoir  near  the  point  where  it 
is  cut  by  a dike.  This  phase  of  the  subject  will  be  considered  at  greater 
length  on  another  page. 

From  the  standpoint  of  the  coal  operator,  the  most  important  question 
concerning  the  dikes  is  their  effect  upon  the  quality  of  the  coal  and 
upon  the  cost  of  mining.  It  is  obvious  that  if  a molten  mass  from  50 
to  100  feet  thick  comes  in  contact  with  coal,  the  coal  will  suffer  con- 
siderable change.  If  a coking  coal,  such  as  that  in  the  Deep  River  Field, 
is  cut  by  a large  dike,  it  may  be  changed  into  any  of  the  following 
substances : if  the  coal  is  near  the  surface  where  oxygen  is  abundant,  the 
coal  is  liable  to  be  entirely  consumed,  leaving  in  its  place  only  a bed 
of  ashes;  if  less  oxygen  is  available,  the  coal  may  be  converted  into 
coke;  and  if  the  supply  of  oxygen  be  very  limited  the  coal  may  he  so 
baked  that  it  is  converted  into  anthracite.  In  general,  it  may  be  said 
that  these  processes  go  on  at  different  depths  beneath  the  surface  of  the 
ground,  for  it  may  be  assumed  that  the  supply  of  oxygen  in  the  rocks 
decreases  as  the  depth  below  the  surface  increases,  but  this  increase  is 
doubtless  irregular,  depending  upon  many  conditions  that,  from  the 
surface,  cannot  be  foretold.  Although  it  is  obvious  that  the  supply  of 


48 


THE  DEEP  RIVER  COAL  FIELD 


oxygen  decreases  with,  depth,  it  is  impossible  to  say  at  what  depth 
anthracite  is  produced  or  at  what  depth  the  coal  is  converted  into  coke. 

In  the  Deep  River  Field,  as  far  as  the  writers  have  observed,  the 
coal  has  been  converted  into  anthracite  wherever  it  has  been  cut  by 
a dike;  therefore,  it  seems  probable  that  when  the  intrusions  took  place 
the  coal  that  now  shows  at  the  surface  was  buried  beneath  hundreds,  if 
not  thousands,  of  feet  of  other  rocks  belonging  to  the  ISTewark  group, 
which  have  been  removed  in  the  general  erosion  of  the  region.  As 
erosion  progresses  so  slowly  that  a man  can  seldom  see  in  his  lifetime 
any  appreciable  change  in  the  earth’s  surface,  due  to  this  agency,  the 
intrusion  must  have  taken  place  millions  of  years  ago  and  probably 
soon  after  the  rock-making  materials  were  deposited. 

As  the  dikes  may  not  only  affect  the  quality  of  the  coal  in  a 
narrow  belt  on  either  side,  but  may  also  in  places  tilt  the  coal  bed, 
as  the  sandstone  bed  is  tilted  in  PI.  Y-B,  they  may  seriously  affect  the 
mining  of  the  coal.  Every  operator,  therefore,  who  is  contemplating 
the  opening  of  a mine  should  carefully  study  and  map  the  dikes,  as  they 
show  at  the  surface,  so  that  he  may  have  some  idea  of  what  he  is  liable 
to  encounter  at  a depth  in  the  mine,  and  he  should  also  study  them  with 
the  object  of  obtaining  more  data  than  is  at  present  available  to  the 
writers,  regarding  the  attitude  of  the  dikes  and  the  points  at  which 
they  are  likely  to  intersect  the  coal  bed.  If  the  dikes  are  vertical, 
as  the  writers  have  been  led  to  suppose,  then  they  should  cut  the  coal 
bed  directly  below  their  exposure  on  the  surface,  no  matter  at  what 
depth  the  coal  may  be,  but  if  the  dikes  are  not  vertical,  then  they 
will  not  cut  the  coal  directly  beneath  the  point  where  they  show  at  the 
surface,  but  to  the  right  or  left,  depending  upon  the  inclination  of 
the  dike  and  the  depth  of  the  coal  bed.  It  is  possible,  however,  that 
a dike,  which  in  general  has  regular  walls  and  which  stands  vertically 
at  the  surface,  may  suddenly  cut  across  the  beds  in  such  an  irregular 
way  that  its  position  at  a given  depth  below  the  surface  cannot  be 
predicted  with  any  assurance  whatever.  The  only  case  of  this  kind  that 
was  observed  by  the  writers  is  that  already  described  at  the  dam  of  the 
Sand  Hill  Power  Company  at  Carbonton,  but  those  who  are  familiar 
with  the  habits  of  dikes  know  full  well  that  though  they  may  be  in 
general  extremely  regular  in  trend  and  in  attitude,  they  will  sooner 
or  later  change  their  courses  suddenly  seemingly  without  reason  and 
pursue  a totally  different  course  from  that  followed  by  the  general 
system.  Such  eccentricities  are  to  be  expected  and  the  operator  should 
watch  carefully  for  them  in  order  to  predict  where  the  dikes  may  be 
encountered  in  the  mine.  Those  who  conduct  drilling  operations  or 
who  examine  drill  cores  for  the  purpose  of  determining  the  character 


PLATE  V 


A.  Minute  dikes  cutting  red  sandstone.  These  dikes  which  range  in  thickness 
from  that  of  a knife-blade  up  to  a quarter  of  an  inch  are  exposed  on  the 
Carthage-Mooshaunee  road  a short  distance  west  of  McLennons  Creek. 


B.  Sandstone  tilted  by  a dike.  This  view  in  a cut  of  the  Norfolk  Southern  Railroad 
on  the  southwest  bank  of  Cape  Fear  River  shows  how  a dike  has  tilted  a bed 
of  sandstone  that  a short  distance  away  is  horizontal. 


THE  DEEP  BIVEE  COAL  FIELD 


49 


of  the  rock  penetrated  by  the  drill,  should  watch  carefully  for  indications 
of  dike  material,  as  it  seems  probable  that  many  times  such  material 
has  not  been  recognized  in  drill  cores  and  thus  only  a part  of  the 
information  which  the  core  should  have  yielded  has  been  utilized. 

GEOLOGIC  STRUCTURES 

Geneeal  Statement 

In  almost  the  earliest  reports  on  this  region  the  Newark  group  is 
reported  as  lying  in  a trough  or  syncline.  Professor  Emmons,  in  his 
report  of  1852  (page  119)  refers  to  it  as  follows: 

Tlie  Deep  River  Coal  Field  is  in  the  form  of  a trough.  In  this  coal  field,  the 
uplift  has  been  made  upon  the  northwest  side.  Its  line  of  demarcation  is 
distinct ; while,  upon  the  southeast  side,  there  is  no  outcrop. 

In  the  course  of  the  present  examination  the  idea  of  the  trough-like 
form  of  the  sedimentary  rocks  was  confirmed  in  the  region  represented 
by  the  map  (PI.  I),  and  also  in  a rapid  reconnaissance  which  was  made 
near  the  southern  boundary  of  the  State. 

On  the  line  between  Richmond  and  Montgomery  counties  the  ISTewark 
sandstone,  shale,  and  conglomerate  show  in  nearly  typical  form,  the 
three  formations  described  in  previous  pages  of  this  report  being 
easily  recognized.  The  belt  of  outcrop  has  a width  of  5 or  6 miles  and 
lies  about  4 miles  east  of  Mount  Gilead  in  Montgomery  County.  The 
southeastern  border  of  the  belt  is  clearly  marked  by  Pea  Ridge  which 
is  formed  of  the  crystalline  schist  and  igneous  rocks.  The  boundary 
line  marking  the  base  of  the  Pekin  formation  passes  through  the  village 
of  Covington  which  is  shown  on  most  maps.  In  travelling  from  Mount 
Gilead  southeastward,  one  first  crosses  a belt  of  red  sandstone  and  shale 
of  the  Pekin  formation,  then  a rather  narrow  belt  of  the  Cumnock 
formation  in  which  coal  is  reported,  but  such  reports  could  not  be 
verified,  except  locally  in  pockets  in  the  gray  sandstone,  then  a belt  of 
red  sandstone  and  conglomerate  of  the  Sanford  formation.  Continuing 
southeastward  one  then  crosses  the  formations  enumerated  above  in 
reverse  order.  This  indicates  clearly  that  the  trough  is  fairly  complete, 
and  dips  show  that  it  is  in  the  form  of  an  open  syncline.  The  dips  on 
the  northwest  side  are  very  slight  and  the  width  of  the  outcrop  is 
correspondingly  great,  but  on  the  southeast  side  the  dips  are  somewhat 
steeper,  though  rather  obscure,  and  the  outcrop  correspondingly  narrow. 
It  is  possible  that  there  is  a small  normal  fault  on  this  side  of  the 
syncline  along  the  northwest  base  of  Pea  Ridge,  but  if  so,  it  is  of  small 
displacement. 

dSTo  attempt  was  made  to  follow  the  formations  northeast  of  Pekin 
and  Covington,  and  in  fact  the  outcrops  on  the  divide  between  the  main 


Geol. — 4 


50 


THE  DEEP  KIVEK  COAL  FIELD 


drainage  lines  are  so  badly  obscured  by  sand  and  gravel  tbat  it  is 
extremely  doubtful  whether  this  can  be  done  until  many  drill  holes  have 
been  put  down  to  bedrock.  In  some  places  on  this  divide  the  bed- 
rock is  deeply  covered,  as  for  instance  at  Pinehurst,  a well  which  was 
drilled  for  water  encountered  bedrock  at  a depth  of  195  feet.  The 
red  rocks  of  the  ISTewark  group  were  seen  at  Jackson  Springs  and  on 
the  headwaters  of  Little  River  north  of  Pinehurst,  and  from  these 
occurrences  it  is  assumed  that  the  synclinal  structure  which  shows  so 
clearly  at  Pekin  and  Covington  is  continuous  with  that  at  Carthage,  as 
shown  on  the  map  accompanying  this  report. 

Cakthage  Though 

General  Description. — At  Carthage  the  east  limb  of  the  trough  is 
lacking,  having  been  cut  off  by  the  Jonesboro  fault,  as  explained  later, 
but  the  synclinal  form  is  plainly  apparent  in  the  rather  steeply  sloping 
northwest  side  of  the  trough  and  the  relatively  flat  bottom  which  is 
indicated  by  the  slight  dips  recorded  on  the  Carthage-Sanford  road. 

Prom  Carthage  northeastward  the  trough  is  continuous  and  of 
approximately  the  same  shape  and  width  to  the  vicinity  of  Sanford, 
Cumnock  and  Gulf,  where  it  is  nearly  cut  off  by  a cross-anticline  here 
called  the  Colon  anticline,  which  corresponds  in  position  and  direction 
with  a line  connecting  Woodard’s  Bridge  and  the  Sanford  Waterworks 
on  the  headwaters  of  Lick  Creek,  about  three  miles  east  of  Sanford. 
The  synclinal  character  of  this  end  of  the  trough  is  shown  by  the 
semicircular  shape  of  its  northern  extremity.  With  the  exception  of 
the  offset  in  the  outcrop  of  the  formations  caused  by  the  Deep  River 
fault,  which  has  already  been  described,  the  formations  crop  out  in 
semicircular  belts  from  Gulf  on  the  northwestern  side,  through  Cum- 
nock to  Sanford  on  the  southeastern  side.  The  outcrop  of  the  Cumnock 
formation,  as  previously  explained,  does  not  complete  the  semicircle, 
as  it  pursues  an  easterly  direction  beyond  the  Capital  Highway  and 
is  lost  to  view  in  a disturbance  of  the  rocks  south  of  Colon.  But, 
although  the  Cumnock  formation  does  not  complete  the  semicircle,  the 
structure  is  complete,  as  shown  by  dips  of  the  overlying  rocks  in  the 
vicinity  of  Sanford;  these  dips  clearly  indicate  that  the  semicircular 
structure  prevails  entirely  across  the  trough  and  is  terminated  only 
where  it  is  cut  off  by  the  great  Jonesboro  fault  which  bounds  the 
Hewark  rocks  on  the  southeast.  The  synclinal  structure  about  Sanford 
is  shown  by  westerly  and  southwesterly  dips  for  one  and  one-half  miles 
west  of  town;  by  westerly  dips  on  the  Carthage  road  a little  north  of 
Buffalo  Church;  by  westerly  dips  in  cuts  on  the  Seaboard  Air  Line 
Railway,  one  and  one-half  miles  south  of  Sanford;  by  westerly  dips  in 


THE  DEEP  RIVER  COAL  FIELD 


51 


cuts  on  the  Atlantic  Coast  Line  Railroad  in  the  vicinity  of  the  Lee 
County  courthouse;  by  southwestward  dips  on  the  Osgood  road  two  to 
two  and  one-half  miles  from  town ; by  southwestward  dips  on  the  Poplar 
Springs  Church  road  two  and  one-half  miles  east  of  Sanford;  and  by 
dips  in  the  same  direction  just  north  of  the  Sanford  Waterworks  on 
Lick  Creek  nearly  due  east  of  town.  The  agreement  of  these  dips  and 
strikes  indicates  beyond  question  that  the  general  structure  in  the 
vicinity  of  Sanford  is  synclinal  and  that  the  trough  has  a very  sym- 
metrical end  at  its  northeastern  extremity.  Some  persons  may  object 
to  this  conclusion  on  the  grounds  that,  by  the  writers’  own  statement, 
the  synclinal  point  or  spoon  is  very  much  broken  and  disturbed  by  the 
Deep  River  and  possibly  other  faults,  and  consequently  there  may  he 
grave  doubts  about  it  Over  having  been  a complete  synclinal  end.  To 
those  who  may  consider  olfering  such  a suggestion,  it  may  he  said  that 
the  presence  of  the  longitudinal  faults  does  not  in  any  way  enter  into 
the  question,  for  it  is  perfectly  clear  that  these  faults  were  produced 
after  the  bowing  up  of  the  Colon  anticline  and  consequently  after  the 
formation  of  the  spoon-shaped  point  to  the  syncline. 

East  of  the  Seaboard  Air  Line  Railway  the  outcrop  of  the  Cumnock 
formation  trends  nearly  due  east  for  one  and  one-half  miles,  and  comes 
to  an  end,  as  far  as  surface  indications  are  concerned,  in  a group  of 
dikes  trending  1ST.  20°  W.  The  original  form  of  the  outcrop  between 
the  point  where  it  now  ends  on  Lick  Creek  and  the  point  where  it 
reappears  on  Little  Lick  Creek  probably  will  never  be  known,  but  it  is 
likely  that  in  its  original  form  it  may  have  turned  back  toward  the 
northwest  slightly  and  then  .pursued  a regular  northeastward  course 
approximately  parallel  with  the  northwestern  margin  of  the  field  as 
it  is  today. 

Minor  Structures. — The  general  synclinal  structure  of  the  Carthage 
trough  is  quite  clear  and  unmistakable,  but  some  of  its  subordinate 
structural  features  are  extremely  puzzling.  The  most  pronounced  of 
these  minor  structures  is  the  Deep  River  fault  which  has  been  partly 
described  on  a previous  page.  This  fault  is  easily  recognized  where  it 
offsets  the  contact  of  the  Pekin  formation  and  the  underlying  crystal- 
line schist  and  also  where  it  causes  a corresponding  offset  in  the  outcrop 
of  the  Cumnock  formation  in  the  valleys  of  Deep  River  and  Buffalo 
Creek,  but  beyond  these  recognizable  features  either  to  the  north  in 
the  crystalline  schist  or  to  the  south  in  the  interior  of  the  Carthage 
trough  it  is  probably  impossible  to  trace  it,  as  it  simply  offsets  the 
beds  within  a single  formation,  and  those  lying  on  one  side  of  the  fault 
are  so  like  those  on  the  other  side  that  they  are  indistinguishable.  It 
is  barely  possible  that  the  fault  extends  into  the  trough  only  a few 


52 


THE  DEEP  RIVER  COAL  FIELD 


miles,  as  represented  on  the  map,  but  it  is  more  likely  to  extend  a much 
greater  distance,  possibly  to  the  southern  boundary  of  the  territory 
represented  by  the  map.  The  fault  is  of  the  normal  or  tension  type, 
for  no  other  kind  of  fault  would  produce  such  offsets  in  the  outcrops 
of  the  formations,  as  have  been  described  here.  It  is  the  same  type 
as  that  of  the  great  Jonesboro  fault  which  bounds  the  Newark  rocks  on 
the  southeast  and  probably  it  was  produced  at  the  same  time  and  by 
the  same  force  that  produced  the  larger  fault.  The  character  of  the 
fault  and  its  effect  upon  the  adjacent  rocks  are  shown  in  Tig.  4. 

The  minor  structures  on  the  rim  of  the  Carthage  trough  in  the 
vicinity  of  Carbonton  and  Haw  Branch  are  not  so  well  marked  as  the 
Deep  Biver  fault  and  consequently  the  exact  character  of  the  deforma- 
tion is  a matter  of  conjecture.  The  surface  evidence  of  some  irregu- 
larity in  the  structure  here,  as  described  on  a previous  page,  consists 
of  the  bifurcation  of  the  outcrop  of  the  Cumnock  formation  a short 
distance  west  of  Carbonton  and  the  termination  in  a point  a short 
distance  southwest  of  Glendon  of  the  northernmost  of  these  bands  of 
outcrop.  This  peculiar  configuration  of  the  outcrop,  as  explained  on 
another  page,  can  be  accounted  for  on  the  assumption  that  there  is 
here  either  a minor  fold  on  the  rim  of  the  larger  trough  or  that  the 
rim  is  cut  by  a normal  fault.  As  the  stresses  in  the  earth’s  crust  in 
this  region  were  such  as  to  give  rise  to  faults  rather  than  to  folds,  the 
first  assumption  as  to  the  character  of  the  disturbance  that  produced 
this  bifurcation  of  outcrop  Avill  not  be  considered  further  and  the 
features  showing  at  the  surface  will  be  attributed  entirely  to  faulting. 

The  actual  existence  of  this  fault  has  been  demonstrated  for  only 
a short  distance — from  Carbonton  to  the  Carthage  road  south  of 
Glendon — but  in  order  to  explain  several  other  irregularities  in  the 
boundaries  of  formations,  it  has  been  hypothetically  extended  from  near 
Putnam  to  the  northern  point  of  the  syncline  between  Gulf  and  Cum- 
nock. The  fault  attains  its  greatest  magnitude,  in  this  district,  in  the 
vicinity  of  Putnam  where  the  displacement  is  probably  1,700  feet 
(4,  Fig.  2).  It  appears  to  decrease  gradually  in  magnitude  toward 
the  northeast,  until  it  dies  out  probably  before  it  reaches  the  outer 
margin  of  the  Pekin  formation  east  of  Gulf.  The  effect  of  this 
movement  on  the  outcrop  of  the  various  formations  involved  is  shown 
graphically  by  a number  of  sections  in  Figure  2 which  are  supposed  to 
represent  the  rocks  as  they  would  appear  in  deep  trenches  cut  directly 
across  the  course  of  the  fault  at  several  places  between  Horseshoe  Bend 
of  Deep  River  and  Carbonton.  In  considering  the  effect  of  this  fault 
on  actual  mining  conditions  in  the  field  it  should  be  clearly  understood 
that  northeast  of  Carbonton  the  existence  of  a fault  as  well  as  its 


THE  DEEP  RIVER  COAL  FIELD 


53 


location  are  almost  entirely  hypothetical  and  may  or  may  not  be  correct. 
As  this  fault  passes  through  the  site  of  the  old  village  of  Carbonton, 
it  will  be  called  the  Carbonton  fault. 

As  shown  in  the  various  cross-sections  of  the  fault,  the  stresses  which 
produced  it  acted  at  right  angles  to  the  course  of  the  fault  and  resulted 
in  stretching  this  part  of  the  crust  of  the  earth.  In  this  stretching 
process  the  stresses  accumulated  until  they  reached  the  elastic  limit 
of  the  rocks  and  then  a fault  ensued  and  the  movement  on  the  fault 
plane  (indicated  by  arrows)  was  such  as  to  cause  the  rocks  to  occupy 
a wider  belt  than  they  did  before  the  break  occurred.  This  widening 
of  the  belt  of  outcrop  was  accomplished  by  the  upward  movement  along 
the  inclined  plane  of  the  fault  of  the  block  of  the  earth’s  crust  on  the 
southeast,  with  respect  to  the  block  on  the  northwest  side  of  the  break. 

It  is  probable  that  there  are  faults  in  this  field  other  than  those 
shown  on  the  map,  but  if  so  they  are  doubtless  of  a lower  order  of 
magnitude.  Several  small  faults  have  been  reported  as  having  been 
encountered  in  mining,  but  these  faults  generally  have  a displacement 
of  only  a few  feet.  Faults  of  this  magnitude  are  serious  obstacles  in 
mining  but  they  are  difficult  to  recognize  at  the  surface.  All  of  these 
faults  are  of  the  normal  variety,  but  they  do  not,  according  to  report, 
offset  the  rocks  in  all  cases  in  the  same  direction  and  to  the  same  amount. 
Faults  that  are  due  to  the  stretching  of  the  earth’s  crust  do  not  always 


■< — A. 


B 


Fig.  3.  Diagram  showing  various  lorms  that  normal  fault  may  assume. 


54 


THE  DEEP  RIVER  COAI,  FIELD 


have  the  upraised  side  on  the  southeast ; it  may  be  on  the  northwest, 
hut  in  that  case  the  plane  of  the  fault  will  incline  in  the  same  direction, 
so  that  when  the  movement  is  completed  the  rocks  will  occupy  a greater 
width  of  outcrop  than  they  did  before.  The  diagram  in  Fig.  3 shows 
how  faults  of  this  type  may  slope  in  either  direction,  but  the  direction 
of  movement  will  always  be  the  same  with  regard  to  the  inclination  of 
the  fault  plane. 

There  are  some  slight  irregularities  in  the  coal  bed  shown  in  the 
Cumnock  and  Carolina  mines.  In  the  former  the  dip  ranges  from 
about  22  degrees  near  the  outcrop  to  about  sixteen  degrees  in  the  lowest 
workings  which,  of  course,  are  approaching  the  bottom  of  the  trough. 
The  coal  bed  in  the  Carolina  mine  has  not  been  mined  far  enough  to 
reveal  much  regarding  the  structure  of  the  coal  bed,  hut  there  is  one 
thing  that  stands  out  very  prominently,  and  that  is  that  the  dip  in  the 
main  entry  is  only  about  ten  degrees.  There  seems  to  be  no  indication 
on  the  surface  of  a lighter  dip  of  the  coal  bed  as  a dip  of  twenty 
degrees  was  measured  in  a cliff  about  half  a mile  southwest  of  the  mine 
and  all  of  the  observed  dips  in  the  surrounding  rocks  agree  with  this 
observation.  The  only  explanation  that  seems  at  all  reasonable  is  that 
the  mine  has  been  opened  in  a gentle  flexure  in  which  the  dip  is  only 
ten  degrees,  but  that  on  driving  the  entries  beyond  this  small  fold, 
the  regional  dip  of  about  twenty  degrees  will  be  encountered. 

The  Colon  Cross-Structure 

The  fact  that  the  Carthage  trough  terminates  abruptly  a few  miles 
northeast  of  Cumnock  and  Sanford,  as  previously  described,  implies 
the  presence  of  some  sort  of  a cross-structure  at  this  place,  because  a 
synclinal  trough  can  come  to  an  end  suddenly  only  by  being  cut  off 
by  a fault  or  raised  by  a cross-anticline  which  effectually  destroys  the 
synclinal  character.  It  is  evident,  therefore,  that  a cross-structure  is 
required  to  explain  the  abrupt  termination  of  the  Carthage  syneline, 
but  the  exact  character  of  the  cross-structure  is  a matter  of  some  doubt. 
If  one  were  to  judge  only  by  the  spooning-out  of  the  general  synclinal 
trough  toward  the  northeast,  one  would  not  hesitate  to  say  that  the 
cross-structure  must  be  anticlinal  in  character,  but  the  break  in  the 
outcrop  of  the  Cumnock  formation  as  well  as  other  features  of  less 
importance,  seem  to  indicate  that  faulting  must  at  least  have  played 
some  part  in  producing  the  features  that  we  find  today. 

The  outcrop  of  the  Cumnock  formation,  as  described  on  a previous 
page,  does  not  indicate  an  anticline  entirely  across  the  trough,  as  all 
trace  of  this  formation  was  last  seen  at  the  system  of  dikes  crossing 
Lick  Creek  about  a mile  south  of  Colon.  From  Cumnock  to  the  dikes 


PLATE  VI 


A.  Hydro-electric  plant  at  Carbonton.  The  dark  shale  below  the  dam  dips  slightly 
to  the  right  or  northwest.  Camera  rests  on  the  dike  shown  below. 


B.  Dike  cutting  shale  irregularly.  The  dike  is  exposed  in  the  river  bank  near 
the  end  of  the  dam  shown  above. 


THE  DEEP  RIVER  COAL  FIELD 


55 


mentioned  above,  the  Cumnock  formation  pursues  a fairly  direct  course 
and  dips  to  the  south,  as  it  should  if  it  formed  the  southwestern  limit 
of  a cross-anticline,  but  the  absence  of  a nearly  parallel  band  of  outcrop 
a short  distance  to  the  northeast  shows  that  the  anticline  is  not  complete, 
or  possibly  that  it  has  been  complicated  by  faulting.  The  basis  for 
the  assumption  of  a cross-fault  is  as  follows: 

(1)  The  disappearance  of  the  Cumnock  formation  when  it  reaches 
the  system  of  dikes,  shown  on  the  map,  two  and  three-quarter  miles 
east  of  Sanford. 

(2)  The  curious  coincidence  of  the  trend  of  these  dikes  directly 
toward  the  sharp  angle  in  the  lower  boundary  of  the  Pekin  formation, 
where  it  turns  from  a northwest-southeast  to  a northeast-southwest 
direction. 

(3)  The  discordance  in  the  dip  and  strike  of  the  rocks  on  the  two 
sides  of  the  belt  of  dikes,  the  dips  on  the  northeast  side  being  at  right 
angles  to  those  on  the  southwest  side. 

(4)  The  apparent  offset  in  the  outcrop  of  the  Cumnock  formation 
from  the  point  already  described  about  one  mile  south  of  Colon  to 
the  prolongation  of  the  belt  of  outcrop  extending  from  Lockville  south- 
westward  parallel  with  and  about  one  and  one-half  miles  distant  from 
the  line  marking  the  base  of  the  Pekin  formation. 

From  the  statements  just  made  it  must  be  evident  to  all  readers 
that  the  writers  are  not  in  possession  of  sufficient  evidence  to  determine 
the  form  and  character  of  the  cross-structure  at  Colon,  but  that  the 
evidence  at  hand  points  to  an  anticline  that  has  subsequently  been  cut 
longitudinally  by  a fault. 

The  Corinth  Trough. — The  structure  of  the  trough  east  and  north 
of  Colon,  as  far  as  the  evidence  obtained  by  the  writers  is  concerned, 
is  comparatively  simple,  consisting  of  a trough  of  syncline  of  folding 
or  deposition,  which  later  has  been  cut  near  its  middle  by  a longitudinal 
normal  fault.  The  resultant  structure  is  that  of  a monoclinal  block 
of  the  earth’s  crust  in  which  the  dips  are  fairly  constant  in  amount  and 
uniformly  toward  the  southeast  across  the  entire  remaining  part  of  the 
trough.  There  are  some  minor  complications  on  the  northwest  side 
of  the  trough,  in  the  vicinity  of  Deep  Kiver,  but  at  the  present  time 
these  are  not  well  enough  known  to  permit  of  an  explanation. 

Jonesboro  Fault.— One  of  the  most  prominent  structural  features 
of  the  Deep  River  coal  field  is  the  great  fault  which  bounds  the  field 
on  the  southeast  side.  As  this  fault  does  not,  in  the  territory  examined 
by  the  writers,  pass  through  any  town,  there  is  some  difficulty  in  finding 
an  appropriate  name,  but  as  it  passes  through  the  northern  outskirts  of 
Jonesboro  and  is,  therefore,  named  the  Jonesboro  fault.  Another 


56 


THE  DEEP  EIVEE  COAL  FIELD 


reason  for  applying  this  name  is  that  the  fault  is  exceptiontlly  well 
exposed  in  a cut  of  the  Atlantic  Coast  Line  Railroad  a few  hundred 
feet  southeast  of  the  Lee  County  courthouse  which  is  located  midway 
between  Jonesboro  and  Sanford. 

The  actual  contact  of  the  Hewark  sandstones  and  the  schist  on  the 
southeast  side  of  the  trough  can  be  seen  in  very  few  places  in  this  field, 
but  in  the  railroad  cut  mentioned  above  it  is  as  well  exposed  as  one 
could  expect  in  rocks  as  soft  and  friable  as  either  the  weathered  schist 
or  the  sandstone.  This  contact  is  shown  in  PL  VII.  As  usual  in  such 
faults,  there  is  not  a clean-cut  line  of  contact,  but  the  contact  can  he 
located  within  a very  few  feet.  On  PL  VII  the  nearly  horizontal  red 
sandstone  can  be  seen  on  the  left,  extending  to  about  the  middle  of 
the  plate  where  it  is  cut  off  by  the  fault,  hut,  as  previously  stated,  the 
break  is  not  a clean  one  and  some  fragments  of  sandstone  may  be  found 
to  the  right  of  this  line.  The  right  half  of  the  plate  shows  crushed  and 
contorted  schist  which  evidently  has  suffered  greatly  when  the  faulting 
took  place  and  in  recent  time  as  been  deeply  affected  by  the  weather. 
This  zone  of  crushed  and  weathered  schist  has  a width  of  about  eighty 
feet,  but  at  the  southern  end  of  the  cut  grades  into  fresh  schist. 

The  Jonesboro  fault  was  next  seen  southwest  of  the  type  locality 
at  the  point  where  it  crosses  the  Seaboard  Air  Line  Railway.  This 
occurs  in  a cut  about  1,U00  feet  north  of  the  highway  bridge  over  the 
railroad  on  the  Jonesboro-Tramway  road.  In  the  cuts  at  and  north  of 
the  bridge  the  schist  is  so  deeply  weathered  that  it  has  lost  its  schistose 
character  and  it  is  quite  difficult  to  determine  the  exact  position  of 
the  fault,  but  the  presence  of  a great  mass  of  quartz  on  the  west  side 
of  the  track  makes  it  certain  that  the  schist  extends  at  least  900  feet 
from  the  bridge.  On  this  basis  and  also  on  the  basis  of  red  sandstone 
and  shale  a little  farther  north,  the  line  was  drawn  as  shown  on  the  map 
and  it  is  probably  correct  to  within  fifty  feet. 

Southwest  of  the  place  where  the  fault  crosses  the  Seaboard  Air 
Line  Railway  the  country  is  deeply  covered  with  white  sand  and  no 
trace  of  the  fault  could  be  found  for  a distance  of  nine  miles,  although 
its  supposed  position  was  crossed  at  a number  of  places,  but  the  sand 
is  so  deep  and  the  dissection  by  the  streams  so  slight,  that  no  exposure 
of  bedrock  could  be  found.  The  fault  was  approximately  located,  how- 
ever, on  a road  leading  southeast  from  Lamms  Grove  Church  at  a 
distance  of  about  one  mile.  Here  the  blanket  of  sand  is  removed  for 
a short  distance,  leaving  the  schist  quite  well  exposed.  Ho  red  sand- 
stone was  seen,  so  the  line  as  drawn  on  the  map  should  be  regarded 
only  as  a provisional  location,  and  the  actual  position  may  be  somewhat 
farther  to  the  northwest. 


THE  DEEP  EIVEE  COAL  FIELD 


57 


The  actual  position  of  the  Jonesboro  fault  was  determined  a few 
miles  farther  southwest  on  the  Carthage-Cameron  road  which  leaves 
the  main  Sanford  road  three  and  one-half  miles  southwest  of  Lamms 
Grove  Church.  On  this  road  at  a distance  of  one  and  one-half  miles 
from  the  Sanford  road  the  actual  contact  of  the  shale  of  the  Newark 
group  and  the  schist  can  be  plainly  seen  by  the  side  of  the  road.  The 
contact  here  is  as  definite  as  that  which  has  already  been  described 
in  the  cut  of  the  Atlantic  Coast  Line  Railway,  north  of  Jonesboro. 

Southwest  of  the  Cameron  road  no  exposures  of  the  Jonesboro  fault 
could  be  found  within  the  limits  of  the  territory  represented  by  the 
map,  although  search  for  it  was  carefully  made  as  far  to  the  southwest 
as  the  Carthage- Vass  road.  The  Newark  rocks  are  exposed  just  west 
of  the  Carthage-Pinehurst  road,  but  southeast  of  that  road  the  sand 
covers  everything  and  no  bedrock  could  be  found. 

East  of  Jonesboro  the  position  of  the  fault  is  much  more  easily 
determined  than  it  Avas  possible  to  do  west  of  that  place.  The  fault 
was  first  located  east  of  Jonesboro  near  the  Sanford  Waterworks  on 
the  headwaters  of  Lick  Creek.  The  exact  contact  was  not  seen  here,  but 
rocks  associated  with  the  schist  show  at  the  creek  crossing  a few  hundred 
feet  north  of  the  waterworks  and  a short  distance  beyond  the  creek  red 
sandstone  of  the  Newark  group  is  well  exposed.  This  gives  the  position 
of  the  fault  with  a possible  error  of  less  than  100  feet. 

East  of  the  waterworks  the  trace  of  the  fault  was  not  crossed  until 
it  reached  Poplar  Springs  Church.  On  the  Sanford  road  leading  to 
this  church  the  bedrock  east  of  the  crossing  of  Lick  Creek  is  greatly 
obscured  especially  on  the  upland  by  quartz  gravel  which  is  so  abundant 
that  it  conceals  all  other  kind  of  rock.  This  condition  prevails  to  the 
road  crossing  within  a few  hundred  feet  of  the  church.  Here  the 
gravel  is  replaced  by  a deep  red  soil  which  at  first  was  taken  by  the 
writers  to  be  the  residual  soil  left  from  the  decay  of  red  shale,  but 
on  close  examination  a small  quartz  vein  was  found  in  a gulley  about 
300  feet  northeast  of  the  church.  This  definitely  fixes  the  red  clay  as 
being  derived  from  the  schist  instead  of  from  clay  of  the  Newark  group 
and  consequently  the  trace  of  the  fault  must  be  at  or  somewhat  to  the 
north  of  the  road  crossing  mentioned.  The  distance  from  the  red  clay 
to  the  fault  is  entirely  hypothetical,  but  judging  from  the  position 
of  the  fault  both  to  the  west  and  the  east  of  this  place,  it  probably 
is  only  a short  distance  north  of  the  road  crossing,  as  shown  on  the 
map. 

The  fault  was  next  located  approximately  on  a country  road  leading 
almost  directly  south  from  Ross  Siding  on  the  Norfolk  Southern 
Railroad.  The  fault  crosses  this  road  about  one  and  one-half  miles 


58 


THE  DEEP  RIVEK  COAL  FIELD 


north  of  the  main  road  from  Jonesboro  to  Avent’s  Ferry  across  Cape 
Fear  River. 

The  Jonesboro  fault  is  clearly  marked  where  it  crosses  the  Jonesboro- 
Avent’s  Ferry  road,  about  a mile  northeast  of  Salem  Church.  The 
crystalline  schist  is  here  in  contact  with  a bed  of  conglomerate  in 
the  Sanford  formation,  which  contains  boulders  of  schist  up  to  16 
inches  in  diameter.  The  approximate  position  of  the  fault  was  also 
obtained  at  a point  about  one  and  one-quarter  miles  to  the  northeast 
of  the  point  where  it  crosses  the  road  to  Avent’s  Ferry.  At  least, 
schist  was  found  in  place,  as  marked  on  the  map;  hence  the  fault  must 
be  to  the  northwest  of  this  point. 

No  attempt  was  made  to  determine  accurately  the  place  where 
the  fault  crosses  Cape  Fear  River,  but  its  position  was  quite  definitely 
fixed  where  it  crosses  the  Norfolk  Southern  Railroad  about  three  miles 
northeast  of  the  river.  Here  between  two  cuts  almost  exactly  one  mile 
east  of  Corinth,  the  fault  must  pass,  as  the  cut  to  the  west  discloses 
only  a coarse  boulder  conglomerate,  whereas  the  cut  to  the  east  shows 
only  granite  in  place,  with  a distance  between  the  cuts  of  scarcely  500 
feet.  The  beds  of  conglomerate  dip  towards  the  fault  about  twenty 
degrees,  and  as  southeast  dips  are  continuous  across  the  trough,  it  is 
supposed  that  the  beds  here  exposed  are  about  the  highest  beds  that 
the  writers  saw  in  the  Sanford  formation.  The  boulders  (PI.  IY-B) 
in  the  conglomerate  are  all  granite,  having  been  derived,  in  all  proba- 
bility from  the  great  mass  of  granite  to  the  southeast,  a part  of  which 
is  shown  in  place  in  the  cut  directly  east  of  the  fault. 

The  trace  of  the  Jonesboro  fault,  as  it  is  indicated  on  the  map, 
is  remarkably  regular  and  without  offsets  or  sharp  bends  of  any  kind. 
This  apparently  is  different  from  the  conception  of  the  fault  held  by 
other  writers.  Thus  on  Kerr’s1  geologic  map  of  North  Carolina 
the  southeastern  boundary  of  the  belt  of  Triassic  rocks  is  represented 
as  extremely  irregular,  making  many  sinuous  bends  that  seem  to  have 
more  relation  to  the  surface  configuration  than  they  do  to  the  geologic 
structure.  The  writers  do  not  understand  how  this  boundary  was  located 
by  previous  writers,  but  it  was  possibly  drawn  through  points  at  which 
the  red  rocks  were  seen  to  pass  beneath  the  mantle  of  sand.  The 
present  writers  followed  the  same  plan  at  first,  until  they  discovered 
that  the  actual  contact  of  the  red  rocks  of  the  Newark  group  and  the 
schist  is  in  places  several  miles  southeast  of  the  point  where  the  Newark 

1Kerr,  W.  C.  : Report  of  the  Geological  Survey  of  North  Carolina,  vol.  1,  Physical 

Geography,  resume,  Economical  Geology,  Raleigh,  1S75. 


THE  DEEP  EITEE  COAL  FIELD 


59 


rocks  pass  under  the  cover  of  sand.  After  that  experience  the  sand  was 
regarded  as  entirely  a surface  feature  and  as  having  no  relation  to  the 
real  structure  of  the  region. 


The  Jonesboro  fault  is  what  geologists  generally  call  a normal  fault, 
or  a fault  which  has  been  produced  by  the  stretching  of  the  earth’s 
crust  in  a direction  at  right  angles  to  the  trend  of  the  fault  trace 
until  the  stress  on  the  rocks  was  more  than  they  could  stand  and  they 
are  forced  to  break — this  break  is  the  fault.  In  the  present  case  the 
pull  came  from  the  southeast  or  the  northwest  and  it  accumulated  until 
it  was  strong  enough  to  rend  the  rocks  of  the  ISTewark  group,  several 
thousand  feet  in  thickness  and  also  the  underlying  schist  to  an  unknown 
distance,  hut  probably  to  as  great  if  not  a greater  distance  than  the 
thickness  of  the  ISTewark  group.  As  nature  abhors  a vacuum,  the 
movement  of  the  rocks  on  the  plane  of  a fault  of  this  kind  is  in  such 
a direction  as  will  produce  no  open  spaces  within  the  earth’s  crust, 
but  will  keep  the  outer  shell  intact,  even  though  that  shell  has 
actually  a greater  circumference  after  the  faulting  than  it  had  before. 
The  manner  in  which  this  is  accomplished  is  shown  in  Fig.  4.  A B 
represents  a block  of  the  earth’s  crust  which  is  subject  to  tension,  as 
indicated  by  the  arrows  at  each  end.  The  effect  of  this  tensional 
stress  is  to  stretch  the  rocks  composing  the  block  to  their  elastic  limit 
and  when  that  is  reached  there  will  occur  a break,  as  the  rocks  can 
no  longer  withstand  the  pull.  In  block  A'B',  the  break  has  occurred 
along  the  line  ab  and  the  block  on  the  right  has  moved  up  with  reference 
to  the  block  on  the  left,  or  the  block  on  the  left  has  moved  down. 
As  the  plane  of  the  fault  inclines  from  the  perpendicular  toward 
the  right  at  the  top  and  the  left  at  the  bottom  it  naturally  follows 
that  a movement  such  as  is  indicated  by  the  arrows  in  block  AB  will 
tend  to  lengthen  the  block  as  the  distance  from  A'  to  B'  is  manifestly 
greater  than  that  from  A to  B.  If  the  fault  plane  had  inclined  to  the 
left  at  the  top  and  the  right  at  the  bottom  then  movement  such  as  has 


60 


THE  DEEP  EIVEE  COAL  FIELD 


been  described  would  have  been  due  to  compression  rather  than  tension 
and  the  result  of  a break  would  be  to  shorten  the  earth’s  crust.  As 
there  is  little  indication  of  compressive  stresses  having  been  operative 
it  is  evident  that  the  Jonesboro  as  well  as  the  Deep  River  fault  are  of 
the  type  represented  in  Fig.  4,  the  fault  plane  in  each  case  inclining 
at  the  top  toward  the  upraised  block,  but  the  indications  in  the  field 
are  that  the  inclination  of  these  fault  planes  is  not  great. 

Histoey  of  the  Development  of  Geologic  Stbuctube 

General  Statement. — The  writers  are  not  prepared  to  outline  the 
complete  history  of  the  development  of  the  geologic  structure,  but 
certain  phases  of  that  history  seem  to  be  quite  well  shown  in  the  Deep 
River  Field,  and  others  are  suggested  which  seem  to  be  worth  stating. 
In  departing  to  a certain  extent  from  the  accepted  opinions  regarding 
the  manner  of  deposition  of  the  Newark  group  and  the  stresses  that 
subsequently  have  developed  in  the  rocks  and  have  deformed  them, 
the  writers  are  aware  that  they  are  entering  a field  in  which  other 
geologists  have  worked  much  more  extensively  and  have  arrived  at 
very  different  conclusions,  still  the  structural  features  here  are  such 
as  seem  to  call  for  a different  explanation.  The  writers  merely  offer 
the  explanation  that  is  the  simplest  and  still  at  the  same  time  the 
one  that  seems  to  be  adequate  to  account  for  the  features  in  question. 

It  is  impossible  to  visualize  the  conditions  under  which  the  Newark 
materials  were  deposited.  Many  geologists  have  regarded  the  present 
structural  features  as  due  to  subsidence  during  deposition,  either  in 
the  form  of  a synclinal  trough  or  as  a tilted  and  faulted  block.  The 
writers  are  not  prepared  to  deny  that  such  movements  have  occurred, 
but  the  field  relations  are  such  that  it  seems  absolutely  certain  that 
the  formation  of  the  Jonesboro  fault  was  the  last  episode  in  the 
history  of  the  development  of  the  structure  of  this  region,  for  the 
fault  cuts  all  of  the  other  structures;  this  it  could  not  do  were  it  not 
the  latest  feature  to  have  been  produced.  If  the  formation  of  the 
Jonesboro  fault  is  later  than  the  formation  of  the  other  features, 
it  is  obvious  that  it  cannot  have  influenced  in  any  way  the  erosion 
of  the  adjacent  region  and  the  transportation  of  the  coarse  material 
to  the  scene  of  deposition  in  the  Newark  trough. 

According  to  the  data  accumulated  during  the  study  of  the  Deep 
River  Coal  Field,  the  development  of  the  present  structural  features 
may  be  divided  roughly  into  three  separate  and  distinctive  episodes, 
as  follows : 

(1)  Deformation  accompanying  sedimentation. — Geologists  who  have 
studied  the  Newark  group  in  the  Appalachian  region  generally  believe 


Jonesboro  fault  in  railroad  cut.  This  exposure  is  in  a cut  of  the  Atlantic  Coast  Line  near  the  Lee  County  Courthouse.  The  fault  brings  red  sandstone 
of  the  Sanford  formation  on  the  left  in  contact  with  badly  decomposed  and  contorted  schist  on  the  right. 


THE  DEEP  EIVEE  COAL  FIELD 


61 


that  these  formations  were  deposited  on  a subsiding  surface  and 
that  as  time  progressed  the  subsidence  became  more  and  more  pronounced 
and  at  the  same  time  the  land  surtace  on  either  side  was  elevated  more 
and  more,  enabling  erosion  to  iurmsh  not  only  more  material  to  be 
deposited,  but  much  coarser  material,  consisting  generally  of  boulders 
several  feet  in  diameter.  Authorities  are  divided  in  their  opinions, 
some  holding  that  the  subsidence  took  the  form  of  a syncline  of  deposi- 
tion, and  some  that  the  subsidence  was  due  to  the  dropping  or  the 
tilting  of  blocks  of  the  earth’s  crust  which  had  been  separated  from 
one  another  by  great  faults. 

The  writers  believe  that  similar  movements  accompanied  the  deposi- 
tion of  the  various  formations  constituting  the  Newark  group  in 
the  Deep  River  Field,  but  the  problem  is  whether  the  subsidence  was  of 
the  nature  of  a syncline  or  of  tilted  and  depressed  blocks.  If  it  were 
the  latter  then  some  trace  of  the  faults  which  accompanied  and  made 
possible  the  tilting  of  the  blocks  should  be  found.  The  only  fault  that 
has  affected  the  trough  throughout  its  entire  extent  is  the  Jonesboro 
fault,  but  it  has  been  shown  that  this  fault  truncates  some  of  the 
important  structures  of  the  field  and  consequently  it  must  have  occurred 
long  after  the  rocks  were  laid  down  and  after  they  were  deformed  in 
certain  ways.  In  the  light  of  this  evidence  the  writers  have  concluded 
that  faulting  did  not  play  an  important  part  in  the  original  deepening 
of  the  troughs.  Even  with  this  point  settled  there  is  still  considerable 
uncertainty  in  the  minds  of  the  writers  as  to  whether  the  troughs 
are  the  result  of  simple  downward  pressure  or  whether  they  are  ihe 
result  of  horizontal  compression.  As  there  is  little  if  any  evidence 
concerning  this  phase  of  the  subject,  it  will  be  dismissed  as  one  of 
those  questions  which  at  the  present  time  are  unanswerable. 

(2)  Torsional  stresses  resulting  in  cross-structures. — The  next  episode 
of  a structural  character  that  followed  the  close  of  sedimentation  in 
this  trough  was  a movement  that  produced  the  cross-structures  that 
are  observable  today.  The  most  pronounced  structure  of  this  character 
is  the  Colon  cross-anticline  which  seemingly  is  responsible  for  the 
northeast  spoon-shaped  termination  of  the  Carthage  trough.  As 
explained  before,  synclinal  structure  is  visible  from  the  northwest  side 
of  the  trough  at  Carbonton  to  the  Jonesboro  fault  south  of  Sanford. 
It  is  inconceivable  that  a syncline  of  deposition  could  have  such  a 
symmetrical  end,  unless  it  terminated  the  area  of  deposition,  but  here 
it  occurs  near  the  middle  of  the  length  of  the  original  trough,  without 
leaving  any  evidence  that  could  be  interpreted  as  indicating  a difference 
in  the  character  or  amount  of  material  deposited  in  one  part  of  the 
trough  from  that  deposited  in  another. 


62 


THE  DEEP  RIVER  COAL  FIELD 


With  the  cross-structures  must  be  classed  also  the  dikes  of  the  region 
which  in  general  trend  north  twenty  degrees  west.  Along  most  of  the 
dikes  there  is  no  indication  of  movement  in  the  adjacent  rocks,  except 
such  slight  disturbances  as  have  already  been  described  under  the 
heading  Igneous  Rocks.  Although  there  is  little  evidence  of  movement 
on  the  planes  of  the  dikes,  the  great  regularity  of  their  trend  and  their 
close  parallelism  in  certain  zones  indicate  that  there  has  been  some 
controlling  condition  that  determined  their  direction.  The  writers 
can  suggest  no  such  controlling  condition,  unless  it  be  incipient  fissures 
which  the  dikes  have  followed.  If  the  presence  of  such  fissures  before 
the  intrusion  of  the  igneous  material  be  granted,  then  the  origin  of 
the  fissures  remains  to  be  explained.  The  only  suggestion  is  that 
possibly  they  were  the  result  of  torsional  stresses  which  twisted  this 
part  of  the  earth’s  crust  and  produced  the  incipient  openings  that 
later  were  filled  with  the  molten  material  forming  the  dikes.  It  is 
impossible  to  fix  the  relative  date  of  the  igneous  intrusions,  except 
that  they  may  possibly  have  occurred  simultaneously  with  the  produc- 
tion of  the  Colon  cross-anticline  and  before  the  movement  began  that 
resulted  in  the  Jonesboro  fault. 

It  seems  highly  probable  that  the  Colon  cross-anticline  and  the 
system  of  fissures  which  were  followed  by  the  dikes  are  both  the 
result  of  torsional  stresses  which  resulted  from  the  crowding  to  the 
westward  of  the  north  end  of  the  trough  holding  the  Rewark  rocks. 
This  twisting  motion  resulted  in  the  formation  of  the  incipient  cracks 
followed  by  the  dikes,  a buckling  of  the  northwestern  rim  of  the  trough, 
which  produced  the  Colon  cross-anticline  that  is  nothing  more  than  a 
cross  wrinkle  caused  by  the  westward  movement  of  the  northern  part 
of  the  trough,  and  possibly  the  faulting  of  this  anticline  which  resulted 
from  the  same  movement. 

In  the  buckling  movement  just  described  and  the  formation  of 
incipient  cracks,  a fine  of  weakness  was  formed  across  the  trough 
passing  through  the  present  site  of  Colon  and  Woodard’s  Bridge  and 
as  the  rocks  to  the  north  were  crowded  westward  it  seems  altogether 
reasonable  to  suppose  that  a fault  occurred  along  this  line,  allowing  the 
rocks  on  the  north  to  move  to  the  westward  as  compared  with  the 
rocks  on  the  south  of  the  fault.  The  amount  of  this  westward  move- 
ment is  measured  by  the  offset  of  the  formation  and  this  probably 
amounts  to  about  two  and  one-half  miles. 

(3)  Normal  faulting  in  a longitudinal  direction. — The  last  episode 
in  this  succession  of  events  was  the  development  of  the  Jonesboro, 
Deep  River,  Carbonton  and  all  other  faults  of  the  normal  type  that 


THE  DEEP  RIVER  COAL  FIELD 


63 


may  be  found  cutting  the  Newark  rocks  in  a direction  roughly  parallel 
with  the  trend  of  the  troughs. 

The  Jonesboro 'is  the  best  example  of  this  type  of  fault  as  it  extends 
throughout  the  territory  represented  by  the  map  and  is  the  most 
pronounced  displacement  that  is  known  in  the  region.  So  far  as  can 
be  determined  from  the  few  exposures  at  which  this  fault  has  been 
seen,  it  is  a nearly  vertical  break  which  allowed  the  rocks  on  the  south- 
east side  to  move  upward  with  reference  to  those  on  the  northwest  side, 
or  the  rocks  on  the  northwest  side  to  move  downward  with  reference 
to  those  on  the  southeast  side.  This  movement  is  evident  when  one 
considers  the  results  produced  by  it.  All  the  evidence  in  the  field 
goes  to  show  that  the  trough  in  which  the  sediments  of  Triassic  age 
were  deposited  was  once  much  wider  than  it  is  at  the  present  time. 
Before  erosion  had  removed  the  rocks  they  doubtless  extended  farther 
to  the  northwest  and  it  is  certain  that  the  Jonesboro  fault  has  cut 
a strip  of  unknown  width  off  the  southeast  side,  for  the  offset  in  the 
Carthage  and  the  Corinth  basins  is  not  reflected  in  the  course  of  the 
fault  as  it  should  he  if  the  fault  were  a normal  boundary,  and  the 
structures  developed  in  the  Carthage  trough  ran  squarely  against  the 
fault  at  right  angles  which  they  would  not  do  were  the  fault  at  the 
original  margin  of  the  trough  of  deposition.  In  view  of  these  facts 
we  must  conclude  that  previous  to  the  faulting  the  troughs  were  wider 
than  they  are  at  the  present  time  and  that  the  part  to  the  southeast  of 
the  fault  has  been  lifted  high  above  the  other  part  and  has  been  eroded 
long  ago,  so  that  now  no  trace  of  it  remains ; or  the  trough  on  the 
northwest  side  has  been  depressed  several  thousand  feet  and  normal 
erosion  has  removed  the  remnant  of  the  Newark  rocks  on  the  south- 
east side.  Either  movement  would  have  produced  the  same  result, 
namely,  that  the  schist  on  the  southeast  side  is  brought  into  contact 
with  the  highest  beds  of  the  Sanford  formation.  The  amount  of 
displacement  of  the  formations  cannot  be  told  accurately,  but  it  must 
at  least  have  been  sufficient  to  bring  all  of  the  Newark  rocks  above  the 
present  surface  on  the  southeast  side  of  the  fault  and  possibly  a con- 
siderable thickness  of  schist  hence  the  movement  on  the  fault  plane 
must  have  been  not  less  than  the  thickness  of  the  Newark  group  which 
on  a previous  page  has  been  estimated  at  7,000  or  8,000  feet. 

The  character  of  the  fault  and  the  movement  which  has  taken  place 
on  the  fault  plane  is  illustrated  in  Fig.  4.  Such  a break  as  that  here 
illustrated,  if  it  took  place  suddenly,  might  have  produced  a ridge  on 
the  southeast  side  of  the  fault  of  mountainous  proportions.  Geologists 
are  now  generally  agreed,  'however,  that  all  such  movements  have  been 
very  slow,  in  fact  so  slow  that,  had  man  been  upon  the  globe  at  that 


64 


THE  DEEP  RIVER  COAL  FIELD 


time,  lie  might  not  have  been  aware  that  great  crustal  movements  were 
in  progress,  as  the  only  disturbance  he  may  have  felt  was  an  occasional 
earthquake  shock  of  not  very  great  intensity.  If  the  faulting  took  place 
as  slowly  as  indicated  above,  it  is  probable  that  the  action  of  streams 
and  the  weather  wore  down  the  surface  of  the  uprising  mass  as  fast 
or  even  faster  than  it  moved,  and  consequently  no  mountains  were 
produced,  although  the  aggregate  displacement,  due  to  the  faulting, 
is  many  thousands  of  feet. 

THE  COAL 

Thickness  of  the  Coal  Beds 


In  the  present  examination  of  the  Deep  River  Field  very  little  coal 
was  seen.  A great  amount  of  prospecting  and  even  mining  was  done 
in  the  early  days  but  the  old  prospect  pits  and  the  mines  have  generally 
fallen  shut,  so  that  the  coal  is  not  visible  at  the  present  time.  Here 
and  there  on  the  public  roads  or  in  gullies  in  the  fields,  some  coal  may 
be  seen,  but  generally  not  enough  to  enable  one  to  pass  judgment  as  to 
its  quality  or  workability. 

The  Cumnock  mine,  being  the  most  extensive  operation  in  the  field, 
naturally  presents  the  best  opportunity  to  study  the  character  and 
thickness  of  the  coal  beds.  In  the  section  of  the  Egypt  shaft,  published 
by  Captain  Wilkes1  in  1858,  the  thickness  of  the  coal  beds  is  given  as 
follows : 


SECTION  OF  COAL  BEDS  IN  THE  EGYPT  SHAFT 


Ft. 

Coal  - . 4 

Blackband  1 

Coal  1 

Shale 

Coal  

Shale,  black  and  iron  balls  . . 8 

Sandstone,  gray  and  clay  ...  16 

Blackband  1 

Coal 1 


I n 
0 

4 
1 
6 
7 
0 
0 

5 
0 


In  the  early  days,  it  is  believed  that  the  entire  thickness  of  the 
Cumnock  or  upper  coal  bed  amounting,  in  this  section,  to  seven  feet 
six  inches,  was  mined.  Whether  or  not  the  blackband  (carbonate  of 
iron)  was  utilized  in  the  manufacture  of  iron,  the  writers  have  not 
been  able  to  determine,  but  it  seems  possible  that  the  builder.'  of  the 
old  Endor  furnace  had  in  mind,  when  they  chose  this  location,  not  only 
the  nearness  to  a supply  of  fuel,  hut  also  of  a moderate  supply  of  ].rw 


Uleport  of  the  examination  of  the  Deep  River  district.  North  Carolina.  Report  of  the 
Secretary  of  the  Navy,  35th  Congress,  2d  Session,  Senate  Doc.  36,  1S58. 


THE  DEEP  EIVEE  COAL  FIELD 


65 


grade  ore  from  the  Egypt  and  other  mines  of  the  district.  Even  if 
the  ore  were  tried  in  this  furnace  it  must  have  soon  been  discovered  that 
it  was  not  suitable  for  the  manufacture  of  iron  as  it  is  associated  with 
and  probably  largely  impregnated  with  phosphate  of  iron  which  occurs 
in  nodules  in  the  associated  shale. 

The  bad  reputation  which  this  coal  had  in  the  early  days  is  probably 
due  to  the  fact  that  both  benches  of  the  coal  were  mined  and  it  is 
equally  probable  that  some  of  the  tests  which  are  reported  to  have 
resulted  disastrously  were  made  on  coal  from  the  lower  bench,  as  this 
coal,  as  shown  in  the  table  of  analyses,  has  an  ash  content  of  30  or  more 
per  cent. 

The  present  writers  measured  the  coal  bed  in  a room  in  the  Cumnock 
mine  directly  above  Slope  USTo.  1 ; at  one  place  it  has  a thickness  of 
three  feet  five  inches  and  at  another,  three  feet  seven  inches.  These 
measurements  are  of  the  entire  upper  bench,  including  at  the  bottom 
some  coal  which  is  more  bony  than  that  which  overlies  it.  Mr.  J.  J. 
Forbes,1  of  the  IT.  S.  Bureau  of  Mines,  gives  the  following  as  the  type 
section  of  the  two  benches  of  coal  in  the  Cumnock  mine : 

TYPE  SECTION  OF  THE  COAL  BED  IN  THE  CUMNOCK  MINE 


(J.  J.  Forbes) 


Coal 

Boue  ..... 
Blaekband  .... 

Coal 

Bone  ..... 

Coal 

Bone  ..... 
Coal  with  thin  layers  ot  shale 


Ft. 

3 

1 


1 


In. 

3% 

3 
6 

10 

o 

4 
3 
0 


Total  bed  . 
Total  coal 


7 7 y2 

5 5% 


In  cutting  the  samples  of  coal  in  this  mine  for  analysis,  Mr.  Forbes 
measured  the  following  section  of  the  upper  bench  of  the  coal  bed 
(see  Fig.  5)  : Coal  3 feet  (analysis  Ho.  85446),  underlain  by  4 V2 

inches  of  bone,  in  room  1,  off  Ho.  1 rise;  coal  3 feet  3%  inches  (analysis 
Ho.  85447)  underlain  by  3 inches  of  bone,  in  room  10,  off  right  side  of 
Ho.  1 slope;  coal  3 feet  7%  inches  (analysis  Ho.  85448),  underlain 
by  2 inches  of  bone,  in  room  13,  off  Ho.  1 slope;  coal  3 feet  7% 
inches  (analysis  Ho.  85449),  underlain  by  1 inch  of  bone,  in  room  8,  off 
Ho.  1 slope. 


Unpublished  report  by  the  Bureau  of  Mines  to  Col.  Joseph  Hyde  Pratt,  State  Geologist. 


Geol. — 5 


66 


THE  DEEP  KIVEB  COAL  FIELD 


DRILL.  HOLE  NO.  2 


Fig.  5.  Section  of  coal  beds. 


THE  DEEP  EIVER  COAL  FIELD 


67 


In  the  mine  of  the  Carolina  Coal  Company  the  upper  bench  of  the 
Cumnock  coal  bed,  according  to  one  measurement  made  by  the  senior 
writer  at  the  face  of  1 left  entry,  75  feet  from  the  foot  of  the  slope,  is 
3 feet  4 inches  thick.  In  sampling  this  bed  for  analysis  1 inch  of  coal 
at  the  top  was  inadvertently  excluded  from  the  sample.  The  analysis 
of  the  remaining  3 feet  3 inches  of  coal  is  shown  as  analysis  Ho. 
83960  in  the  table  on  p.  96.  Mr.  J.  J.  Forbes,  of  the  Bureau  of  Mines, 
also  obtained  samples  in  this  mine  and  his  measurements  at  the  points 
sampled  are  as  follows  (Fig.  5)  : coal  3 feet  (analysis  Ho.  85590), 
on  1 rib  of  left  air-course,  700  feet  from  the  mouth  of  the  mine;  coal 
3 feet  (analysis  Ho.  85591),  in  Ho.  1 cross-entry,  in  by  slope  air-course. 
Mr.  Forbes  also  took  samples  for  analysis  and  made  measurements  of 


the  lower  bench  of  the  coal  bed  in 

the  Carolina  mine  as 

follows : 

SECTIONS  OF 

LOWER 

BENCH 

OF  COAL  IN  CAROLINA 

MINE 

A 

Ft. 

In. 

B 

Ft. 

In. 

Coali  . 

10 

Coal2 

10 

Bone  . 

1 

Bone  . 

1 

Coali  . 

fi 

Coal2 

11 

Bone  . 

3 

— 

CoaU  . 

. 1 

1 

1 

10 

o 

9 

Sections  A and  B were  measured  in  1 left  entry,  off  main  slope. 

In  1884  H.  M.  Chance  prospected  the  coal  beds  in  the  vicinity  of 
Farmville  (the  Carolina  coal  mine)  quite  thoroughly,  sinking  in  all 
twenty-two  shafts  in  order  to  determine  the  character  and  thickness  of 
workable  beds.  In  one  of  these  shafts  he  found  the  upper  bench  of 
the  Cumnock  coal  bed  to  have  a thickness  of  3 feet,  but  in  all  others 
it  was  very  much  thinner  or  wanting  altogether.  His  final  decision  was 
that  the  upper  bench  of  this  coal  bed — the  one  now  being  mined  on  the 
property  by  the  Carolina  Coal  Company — is  of  no  value.  The  con- 
ditions which  led  to  this  decision  were  probably  due  to  the  fact  that 
the  many  prospectors  who  had  preceded  Chance  in  this  part  of  the 
field,  had  mined  out  most  of  the  coal  along  the  crop  and  what  remained 
had  been  affected  by  caving  or  the  metamorphosing  action  of  dikes  and 
consequently  did  not  show  the  full  thickness  of  the  bed. 

Finding,  as  he  supposed,  that  the  Cumnock  bed  was  here  worthless, 
Chance  directed  his  attention  to  the  Gulf  coal  bed  which  lies  about  30 
feet  below  the  Cumnock  bed.  His  section  of  these  beds  and  the  inter- 
vening measures  is  as  follows : 


1Sampled  for  analysis  No.  85593. 
2Sampled  for  analysis  No.  85594. 


68 


THE  DEEP  BIVEE  COAL  FIELD 


SECTION  OF  COAL  BEDS  AT  FAEMVILLE 


By  H.  M.  Chance 

Feet 

In. 

Coal  i Cumnock  bed 

1 

0 

Shale  and  blackband! 

1 

6 

Clay  and  shale  (estimated) 

10 

0 

Shale  ........ 

5 

0 

Coal 

4 

Shale  and  clay 

6 

0 

Coal 

1 

0 

Shale  and  clay 

4 

0 

Coal  . 

1 

2 

Shale  and  clay  ....... 

3 

6 

Coal,  shaly  i Gulf  bed 

8 

Coal  j 

2 

0 

Shale  in  blocks  ....... 

4 

Clay  

4 

0 

Chance  concluded  that  the  Gulf  coal  bed  is  more  regular  in 

thickness 

and  consequently  more  reliable  than  the  Cumnock 

bed  and 

hence  he 

concentrated  his  operations  on  this  bed  and  mined  more  than  100  tons 
which  were  shipped  to  Ealeigh  for  the  use  of  the  Ealeigh  State  Exposi- 
tion. The  character  of  this  coal  is  shown  by  an  analysis  which  is 
supposed  to  be  of  a sample  representing  about  60  tons  of  coal  from  the 
Gulf  bed.  The  analysis  is  as  follows : moisture,  2.1 ; volatile  matter, 
28.9 ; fixed  carbon,  52.6 ; sulphur,  3.7 ; and  ash,  12.7.  It  is  easy  now, 
with  the  data  at  present  available,  to  understand  that  Chance  was 
entirely  mistaken  in  the  relative  values  of  the  Cumnock  and  Gulf  coal 
beds,  both  as  regards  thickness  of  beds  and  quality  of  the  coal. 

In  addition  to  the  information  which  the  Cumnock  and  the  Carolina 
mines  afford  regarding  the  coal  beds  there  are  the  logs  of  four  deep 
drill-holes  which  have  been  put  down  on  the  Cumnock  property.  These 
sections  are  shown  in  Fig.  1.  The  coal  beds  penetrated  by  the  drill 
are  as  follows  (Fig.  5)  : 


SECTIONS  OF  COAL 

BEDS 

IN  DBILL- 

-HOLES  ON  CUMNOCK  PKOPEKTY 

oreliole  No.  l 

Ft, 

In. 

Borehole  No.  2 

Ft. 

In. 

Coal  . 

3 

10 

Coal 

3 

11 

Bone  . 

4 

Blackband  . 

9 

Blackband  . 

2 

3 

Coal 

1 

3 

Coal  . 

1 

2 

Blackband  . 

1 

1 

Coal  . 

5 

0 

Coal  . 

7 

Bed  . 

7 

7 

Coal  . 

5 

9 

Bed  . 

. . t 

i 

THE  DEEP  KIVEK  COAL  FIELD 


69 


'orehole  No.  3 

Ft. 

In. 

Borehole  No.  4 

Ft. 

In. 

Coal  . 

2 

2 

Coal  and  coke 

4 

0 

Shale,  sandy 

0 

6 

Blackband  . 

1 

4 

Shale,  black 

0 

6 

Coal 

2 

0 

Coal,  bony  . 

4 

Blackband  . 

10 

Coal 

1 

6 

Shale,  black 

6 

Coal,  bony  . 

3 

Coal  . 

6 

0 

Coal  . 

4 

3 

Bed  . 

7 

4 

Bed  . 

6 

7 

It  must  be 

admitted 

that 

different 

measurements 

obtained  on 

the 

upper  bench  of  the  Cumnock  bed  in  the  boreholes  might  be  interpreted 
as  confirming  Chance’s  opinion  that  this  bed  is  too  irregular  in  thickness 
to  be  successfully  mined,  but  when  all  of  the  data  on  thickness  available 
at  Cumnock  and  the  Carolina  mines  are  considered,  then  one  cannot 
help  being  impressed  with  the  apparent  regularity  of  the  upper  bench, 
running  on  the  average  about  3 feet  3 inches  in  thickness  and  that  those 
sections  which  depart  from  this  assumed  normal  section  are  distinctly 
different  and  possibly  are  to  be  explained  by  the  disturbing  influence 
of  dikes.  Usually  the  cores  obtained  in  drilling  are  regarded  as  the  final 
word  regarding  coal  beds,  but  in  this  field  the  core  may  be  seriously 
affected  by  a dike  and  hence  every  such  record  needs  interpretation  by 
a competent  geologist. 

On  the  outcrop  southwest  of  Cumnock  there  are  a few  exposures  of 
the  coal  beds  where  measurements  can  be  obtained  and  a number  of 
caved  prospects  regarding  which  there  was  obtained  some  information 
that  is  considered  reliable.  Some  few  years  ago  a slope  was  sunk  on 
the  principal  coal  bed  from  a point  on  the  outcrop  about  IV2  miles 
nearly  due  west  of  the  Cumnock  mine  by  William  Hill,  then  General 
Manager  of  the  Cumnock  property.  According  to  Mr.  Hill  the  slope 
was  carried  down  in  coal  4 feet  2 inches  thick  to  a point  150  feet  from 
the  mouth  of  the  slope  at  which  the  coal  bed  is  offset  by  a fault.  After 
considerable  money  had  been  spent  in  a fruitless  search  for  the  coal 
bed,  the  project  was  abandoned. 

I11  the  vicinity  of  Gulf  many  prospect  pits  and  so-called  mines  have 
been  opened  on  the  Cumnock  coal  bed,  but  these  have  not  been  kept 
open  and  the  result  is  that  the  pits  have  caved  to  such  an  extent  that 
the  coal  cannot  be  seen.  The  only  place  at  which  coal  is  exposed  at 
the  present  time  in  this  locality  is  in  a recent  cut  (PI.  II-B)  of  the 
Norfolk  Southern  Railroad,  about  2,000  feet  southwest  of  the  railroad 
station  at  Gulf.  The  coal  bed  here  is  badly  crushed  and  weathered, 
but  it  has  the  appearance  of  being  about  4 feet  thick. 


THE  DEEP  RIVEK  COAL  FIELD 


70 


Chance  gives  some  data  regarding  the  coal  beds  at  Gulf.  At  the 
time  of  his  examination  (1884)  the  remains  of  two  old  slopes  were 
found  near  the  boundary  line  between  the  Taylor  and  the  Gulf  proper- 
ties from  which  apparently  considerable  coal  had  been  mined.  The 
slope  on  the  Taylor  farm  was  not  open  so  that  the  coal  could  be  seen, 
so  Chance  sunk  a shaft  nearby  which  struck  the  upper  bench  of  the 
Cumnock  bed  below  water  level.  In  this  shaft  the  coal  bed  measures 
“almost  exactly  3 feet  of  good  clean  coal  with  a slate  roof  and  black- 
band  floor.”  The  analysis  of  an  “average  sample”  taken  from  a ton  of 
mined  coal,  as  reported  by  the  State  Chemist,  is  as  follows : moisture, 
1.7;  volatile  matter,  35.4;  fixed  carbon,  55.4;  sulphur,  2.0;  and  ash, 
5.5.  This  analysis  is  almost  identical  with  some  given  on  page  108  of 
samples  from  the  upper  bench  of  coal  in  the  Cumnock  mine,  except 
that  the  percentage  of  ash  is  less  than  that  shown  in  recent  sampling. 
This  small  percentage  of  ash  is  probably  due  to  the  fact  that  the  sample 
was  picked  coal,  although  intended  to  be  of  average  quality. 

The  coal  bed  opened  on  the  eastern  edge  of  the  Gulf  property,  as 
reported  by  Mr.  Williams,  has  the  following  average  section : 

SECTION  OF  COAL  BED  ON  GULF  PROPERTY 

Ft.  In.  Ft.  In. 

Coal 2 0 to  2 G 

Shale 4 to  6 

Coal 5 to  6 

A sample  of  coal  from  this  bed,  taken  from  a pile  of  about  400  tons 
gave  the  following  analysis : moisture,  1.9 ; volatile  matter,  32.8 ; fixed 
carbon,  59.9 ; sulphur,  1.4 ; and  ash,  4.0.  Chance,  however,  believes 
that  this  analysis  is  not  representative  and  that  the  coal  contains  much 
more  ash  and  sulphur  than  the  analysis  indicates.  This  bed  is  corre- 
lated by  Chance  with  the  bed  which  he  mined  at  Farmville  and  which 
lies  about  30  feet  below  the  Cumnock  bed.  As  the  coal  appears  to  be 
quite  well  developed  here  it  will  be  called  the  Gulf  coal  bed. 

From  the  vicinity  of  Gulf  to  the  old  Black  Diamond  mine  on  Indian 
Creek,  there  is  apparently  little  information  regarding  the  condition  of 
the  coal  beds  at  the  crop  line  or  indeed  back  from  the  outcrop,  as  no 
records  of  diamond  drill-holes  have  been  obtained. 

The  most  recent  report  on  this  part  of  the  field  is  that  of  Chance 
(p.  43)  which  is  as  follows: 

Explorations  made  in  the  past  upon  the  western  part  of  the  Gulf  property 
near  the  Tyson  place  evidently  failed  to  find  the  coal  in  good  condition.  Two 
or  three  slopes  were  sunk  here  at  which  considerable  work  was  evidently  done. 


THE  DEEP  EIVEE  COAL  FIELD 


71 


but  the  reports  not  being  favorable  and  the  appearance  of  the  openings  and 
the  dumps  being  extremely  unfavorable,  I did  not  consider  it  necessary  to 
reopen  these  pits,  especially,  as  much  work  has  recently  been  done  on  this 
property  by  northern  capitalists,  and  as  they  did  not  open  at  these  places 
the  inference  that  the  prospect  was  not  favorable  enough  to  justify  further 
work  received  additional  and  forcible  support.  Moreover  as  the  property 
is  now  being  thoroughly  prospected  by  the  present  owners  (Metropolitan  Bank 
of  Boston),  with  a diamond  drill,  at  a cost  of  probably  three  or  four  times  as 
much  as  was  appropriated  for  this  exploration  of  both  the  Deep  and  Dan 
river  coal  fields,  the  results  so  obtained  will  doubtless  determine  the  value  of 
this  property  independently  of  any  work  that  might  be  done  by  that  State. 

Explorations  on  the  Tyson  and  Palmer  places  had  also  evidently  failed  to 
disclose  the  existence  of  coal  of  workable  quality  and  thickness,  if  we  may 
place  any  faith  in  the  recollections  of  the  residents  (and  in  this  I think  we 
may),  and  as  the  opening  made  on  the  Evans  place  at  the  old  workings,  were 
of  such  a discouraging  character,  I did  not  feel  justified  in  making  any  open- 
ing on  these  intermediate  plantations,  i.e.,  between  the  Gulf  property  and  the 
Evans  place. 

It  is  very  unfortunate  that  the  results  of  drilling  operations  in  the 
vicinity  of  Gulf,  and  from  that  place  south-westward  to  the  old  Black 
Diamond  mine  have  never  been  made  public.  Under  ordinary  con- 
ditions Chance’s  conclusions  regarding  the  character  of  the  coal  bed 
would  be  entirely  justifiable,  but,  owing  to  the  apparently  abnormal 
conditions  in  this  field,  the  writers  are  not  fully  satisfied  that,  because, 
one  man  or  one  group  of  men,  not  thoroughly  acquainted  with  the 
geologic  conditions  of  the  field,  saw  fit  to  advise  no  further  operations 
in  1885,  that  the  field  is  entirely  without  merit  in  1923.  We  do  not 
think  it  entirely  safe  to  come  to  such  a conclusion  without  more  evi- 
dence, and  consequently  the  condition  of  the  coal  bed  in  this  part 
of  the  trough  will  remain  unknown  until  core-drilling  is  done  here  or 
in  adjacent  areas. 

The  Cumnock  coal  bed  has  been  mined  quite  extensively  near  the 
point  where  the  wagon  road  from  Gulf  to  Carhonton  crosses  Indian 
Creek.  This  mine  is  known  as  the  Black  Diamond  mine,  but  by  whom 
it  was  developed  and  operated  the  writers  do  not  know.  It  was 
evidently  in  operation  many  years  ago  as  the  old  openings  have  largely 
fallen  shut  and  the  mine  dump  has  been  almost  completely  covered  by 
a rank  forest  growth.  ISTo  satisfactory  measurement  of  the  thickness 
of  the  coal  bed  could  be  made,  but  Chance,  in  1884,  made  some  reexca- 
vations here  which  throws  some  light  on  the  condition  of  the  coal 
bed.  At  the  old  shaft  Chance  reports  the  following  section: 


72 


THE  DEEP  RIVER  COAE  FIELD 


SECTION  OF  COAL  BED  IN  THE  SHAFT  OF  THE  BLACK  DIAMOND  MINE 


Shale,  clay,  and  decomposed  shale 
Coal,  with  some  shale 
Shale  and  hlackband 
Coal 


Ft.  In. 

32  4 

1 6 

1 6 

2 8 


Chance  makes,  the  following  comment : 

In  the  airway  I found  the  workings  were  also  upon  the  lower  bench,  but 
the  coal  was  not  quite  so  thick  here  as  at  the  shaft  near  the  old  slope.  The 


coal  appeared  to  be  somewhat  variable 

and  it 

was  difficult 

to  select  a 

place  to  make  a measurement.  The  coal 

may  be 

considered  to 

average  as 

follows : 

Ft. 

In.  Ft. 

In. 

Shale  and  coal  .... 

6 to 

10 

Coal 

1 

8 to  2 

0 

Part  of  the  coal  is  poor  and  slaty  and, 

if  the  measurement  included  only 

the  good  coal,  the  figures  would  be  much  smaller. 

The  whole  bed,  therefore, 

may  be  considered  as  showing  an  average 

measurement : 

Ft. 

In.  Ft. 

In. 

Coal  (bench  not  worked) 

1 

2 to  1 

6 

Shale  and  blackband 

1 

6 to  1 

G 

Shale  with  some  coal 

G to 

10 

Coal  (lower  bench) 

1 

6 to  2 

0 

This  bed  is  doubtless  identical  with  the  “Big”  bed  at  the  Gulf,  Egypt, 
and  Farmville,  but  in  a sadly  deteriorated  condition.  The  upper  bench,  which 
at  these  localities  carries  the  best  coal,  is  here  too  thin  to  be  worked,  and 
the  low  bench  is  not  only  thin  but  of  poor  quality,  yielding  very  little  good 
coal. 

Chance’s  condemnation  of  the  coal  bed  at  this  mine  is  based  largely 
on  a question  of  thickness  of  the  coal  bed.  The  question  now  arises, 
was  he  justified  in  his  conclusions?  The  coal  in  the  shaft  of  this 
old  mine  is  a high-rank  anthracite,  as  shown  by  samples  collected  by 
him  and  analyzed  by  the  State  chemist.  The  analysis  is  as  follows : 

ANALYSIS  OF  COAL  FROM  THE  BLACK  DIAMOND  MINE 


Water  at  115  C. 

Per  cent 
4.3 

V olatile  matter 

4.9 

Fixed  carbon 

74.6 

Sulphur 

2.1 

Ash 

14.1 

As  the  coal  in  this  field  is  generally  of  a bituminous  character, 
it  is  evident  that  the  anthracite,  disclosed  by  this  analysis,  is  due  to 
local  metamorphism  by  the  heat  of  a dike  which  cuts  the  coal  bed 
practically  at  the  point  where  the  old  mine  was  situated.  This  inference 
was  verified  by  the  writers  who  found  many  blocks  of  excellent 
anthracite  on  the  mine  dump  and  the  dike  itself  is  visible  on  the  surface 


THE  DEEP  RIVER  COAL  FIELD 


73 


all  about  the  old  workings.  If,  therefore,  the  coal  bed,  after  being- 
converted  into  anthracite  has  a thickness  of  1 foot  2 inches  to  2 feet, 
as  quoted  above,  is  it  not  reasonable  to  assume  that  the  coal  bed,  before 
it  was  metamorphosed  by  the  dike  was  considerably  thicker?  If  this 
is  a reasonable  assumption,  can  these  measurements,  which  are  the 
only  ones  available,  be  used  to  predict  the  thickness  of  the  bed  at 
some  distance  from  the  dike  or  in  the  interior  of  the  trough?  Fortun- 
ately there  is  considerable  data  at  hand  bearing  on  the  shrinkage  of  a 
coal  bed  when  it  is  converted  from  bituminous  coal  to  anthracite,  and 
the  writers  believe  that  the  data  are  in  such  concrete  form  that  they 
may  be  applied  directly  to  this  case. 

In  the  Cerrillos  coal  field  of  Hew  Mexico,  a coal  normally  of 
bituminous  rank  has  been  locally  converted  into  high-rank  anthracite 
by  the  heat  of  a volcanic  sill  which  has  been  injected  into  the  rocks 
a few  feet  above  the  coal  bed.  Where  the  coal  has  been  converted  into 
anthracite  it  has  shrunken  from  4 feet  6 inches  to  2 feet  10  inches  in 
thickness.  A similar  case  is  known  in  Routt  County,  Colorado,  where 
a volcanic  sill  has  changed  a bituminous  coal  11  feet  thick  into  anthra- 
cite 6 feet  6 inches  thick.  The  percentage  of  reduction  in  thickness 
in  these  two  cases  is  nearly  the  same,  but  to  apply  the  results  to  the 
coal  of  the  Deep  River  Field  it  is  necessary  to  know  the  percentage  of 
increase  from  anthracite  to  bituminous.  In  the  Hew  Mexico  coal  it 
amounts  to  60  per  cent  and  in  the  Colorado  coal  to  69  per  cent.  The 
average  of  these  two  is  65  per  cent. 

If  this  rate  of  increase  is  applied  to  the  measurements  given  by 
Chance,  his  figures  would  be  changed  as  follows : 

1 foot  6 inches  multiplied  by  1.65=2  feet  5%  inches. 

2 feet  multiplied  by  1.65=3  feet  3%  inches. 

2 feet  8 inches  multiplied  by  1.65=4  feet  4%  inches. 


On  this  basis  it  seems  quite  probable  that  away  from  the  dikes  the 
coal  in  the  Carbonton  region  will  be  found  thick  enough  to  work,  at 
least  in  the  vicinity  of  the  outcrop.  What  its  thickness  may  be  in  the 
interior  of  the  trough  can  be  told  only  by  deep  drilling. 

The  next  point  at  which  some  information  was  obtained  regarding 
the  coal  is  an  old  prospect  or  mine,  generally  known  as  the  Gardner'u^ 
mine.  This  prospect  is  in  a ravine  on  the  southeast  side  of  the  road 
leading  from  Carbonton  to  Horseshoe  Bend  of  Deep  River  and  about 
2*4  miles  from  the  railroad  station  at  Carbonton.  Here  again  the 
prospect  has  been  opened  where  the  coal  bed  is  cut  by  a dike  and  the 
heat  has  changed  the  coal  into  anthracite.  An  analysis  by  the  State 
chemist  of  a sample  of  the  best  coal  from  this  prospect,  collected  by 
Chance  (p.  40),  is  as  follows: 


74 


THE  DEEP  EIVER  COAL  FIELD 


ANALYSIS  OF  COAL  FROM  THE  GARDNER  MINE 


Per  Gent 


Water  at  115  degrees  0. 

1.7 

Volatile  matter  .... 

6.4 

Fixed  carbon  .... 

80.0 

Sulphur  .... 

2.8 

Ash  .... 

9.1 

The  old  prospect  is  still  open,  exposing  the  coal  bed  which,  according 

to  the  writers’  measurements,  is  as  follows : 

SECTION  OF  COAL  BED  IN  THE  GARDNER  MINE 

Ft.  In. 

Coal  

ii  y2 

Shale,  black 

4 

Coal  

1 3 

2 6% 

As  the  analysis,  quoted  above,  shows  this 

to  be  a good  grade  of 

anthracite,  the  thickness  should  be  increased 

as  follows: 

CORRECTED  SECTION  OF  THE  COAL  BED  IN 

THE  GARDNER  MINE 
Ft.  In. 

Coal  

1 7 

Shale,  black 

4 

Coal  

2 0% 

4 1% 

The  section  of  the  coal  bed  in  this  mine,  as  reported  by  Chance, 
is  different  from  that  measured  by  the  writers.  Chance’s  statement 
(p.  47)  is  as  follows: 


The  total  thickness  of  the  bed.  as  exposed  by  this  drift,  is  about  2 feet  8 
inches  [4  feet  4%  inches,  expanded  measurement]  with  a few  inches  of  very 
slaty  coal  on  top  and  two  (sometimes  three)  slate  partings  from  % inch  to 
1 inch  thick  dividing  the  coal  into  benches  of  very  nearly  equal  size.  The 
lower  part  of  the  bed  is  evidently  high  in  ash ; the  coal  between  the  slate 
partings  is  clean  and  good,  there  being  two  such  layers  respectively  5 and  7 
inches  thick. 

There  are  many  old  prospects  on  the  northwestern  line  of  the  coal 
outcrop  from  the  vicinity  of  Haw  Branch  village  southwestward  for 
a distance  of  two  miles,  but  no  new  data  on  the  condition  of  the  coal 
bed  in  this  part  of  the  field  was  obtained  by  the  writers.  Chance 
states  that  he  opened  some  of  these  old  pits  on  the  Murchison  farm, 
probably  a short  distance  west  of  Haw  Branch  station.  Here  he  found 
6 to  8 inches  of  “slaty  worthless  coal”  overlying  26  to  30  inches  of 
“coal  with  several  thin  slaty  seams.”  Judging  from  the  analysis  given 
by  Chance,  it  is  apparent  that  the  coal  here  has  been  only  slightly 


THE  DEEP  RIVER  COAL  FIELD 


75 


metamorphosed  to  a semibituminous  coal.  In  the  pits  on  the  south- 
west side  of  Deep  River,  on  what  is  now  the  Jones  farm,  he  reports  the 
coal  bed  as  containing  more  shale  than  coal  and  in  general  a worthless 
bed. 

Although  it  seems  possible  that  the  coal  may  be  successfully  mined 
as  far  to  the  southwest  as  the  Gardner  mine,  the  evidence  seems  to  be 
conclusive  that  the  bed  is  deteriorating  in  this  direction  and  that 
somewhere  near  the  place  where  it  crosses  Deep  River  is  the  limit  of 
workable  coal.  There  are  many  rumors  of  coal  farther  to  the  south- 
west, but  the  writers  were  unable  to  verify  them  and  they  very  much 
doubt  the  presence  of  coal  thick  enough  to  work  in  the  territory  drained 
by  McLennon’s  Creek. 

East  of  the  Deep  River  fault,  but  little  is  known  of  the  coal.  On 
Pretty  Creek  just  north  of  the  old  McTver  homestead,  coal  was  mined 
rather  extensively  about  Civil  War  times,  but  the  mines  have  slumped 
shut  and  at  present  no  coal  can  be  seen.  According  to  report,  Charles 
Reeves  reopened  some  of  these  mines  a few  years  ago  and  found  a coal 
bed  2 feet  thick.  As  there  are  no  dikes  known  in  the  vicinity,  it  is 
probable  that  the  thickness  reported  by  Mr.  Reeves  is  the  maximum 
thickness  than  can  be  expected  in  this  region.  An  ambitious  attempt 
was  made  just  before  the  Civil  War  to  develop  the  coal  east  of  this 
fault,  by  a two-compartment  shaft,  located  nearly  a mile  due  west  of 
the  point  where  the  Old  Cumnock  road  branches  off  the  Capital 
Highway,  2%  miles  north  of  Sanford.  There  is  a vague  report 
current  that  this  shaft  is  400  feet  deep,  but  it  is  now  full  of  water  and 
that  rumor  could  not  be  verified.  Mo  trace  of  coal  or  even  black  shale 
was  found  on  the  dump  so  it  seems  probable  that  the  project,  which 
was  abandoned  on  the  breaking  out  of  hostilities,  had  not  been  carried 
to  completion  and  a workable  bed  discovered.  It  seems  incredible 
that  any  company  would  expend  money  enough  to  sink  such  a shaft 
without  preliminary  drilling  to  establish  the  presence  of  a workable 
bed  of  coal,  but  the  writers  could  not  find  any  one  who  knew  of  such 
drilling  having  been  done  or  even  were  aware  of  the  names  of  the 
parties  who  sunk  the  shaft. 

Professor  Emmons,  as  stated  on  another  page,  reports  that  a 10-inch 
bed  of  coal  was  pentrated  by  the  drill  at  a shallow  depth  on  the  farm 
of  Martin  Dyer,  near  the  junction  of  the  old  Cumnock  road  with  the 
Capital  Highway.  So  far  as  known  to  the  writers  this  constitutes  all 
of  the  data  on  the  coal  west  of  the  Capital  Highway.  It  is  manifestly 
inadequate  as  a basis  for  a prediction  as  to  the  tonnage  available  and 
the  extent  of  the  field,  but  it  is  given  in  detail  so  as  to  show  clearly 
how  meager  the  information  is  and  how  necessary,  before  new  mining 


76 


THE  DEEP  EIV EE  COAL  FIELD 


enterprises  are  inaugurated,  to  drill  back  of  the  outcrop  so  as  to  know 
definitely  the  thickness  and  character  of  the  coal  beds  and  their  depth 
below  the  surface  of  the  ground. 

East  of  the  Capital  Highway  and  as  far  northeastward  at  least  as 
Haw  River  no  coal  more  than  3 , inches  in  thickness  has  been  reported 
on  what  is  regarded  as  reliable  authority.  In  view  of  this  fact  it  is 
highly  probable  that  coal  of  workable  thickness  does  not  occur  in 
this  region. 

Extent  of  Workable  Coal  and  the  Available  Tonnage 

From  the  evidence  just  given  regarding  the  conditions  of  the  coal 
beds  on  the  outcrop  and  in  mines  and  drill-holes,  there  seems  to  be 
little  question  that  one  bed,  at  least,  is  of  workable  thickness  along  the 
outcrop  from  the  Deep  River  fault  to  Haw  Branch,  a distance  of  11 
miles.  East  of  the  Deep  River  fault  the  evidence  is  so  meager  regarding 
the  presence  of  workable  coal  that  one  does  not  seem  justified  in 
including  any  of  this  territory  in  a probable  coal  field,  until  the  presence 
of  such  coal  has  been  demonstrated  by  extensive  prospecting  with 
pick  and  shovel  or  better,  with  a core  drill. 

The  amount  of  available  coal  in  this  field  depends  upon  several 
factors,  some  of  which  are  known  with  some  degree  of  certainty  and 
others  are  unknown  or  are  so  little  known  that  any  statement  regarding 
them  must  partake  more  or  less  of  the  character  of  a guess.  Oue  of 
the  greatest  of  the  unknown  factors  is  the  shape  and  depth  of  the  trough 
holding  the  Hewark  rocks.  Some  have  assumed,  but  on  what  grounds 
the  writers  have  never  found  out,  that  the  basin  at  Cumnock  is  nearly 
circular  in  shape  and  some  manuscript  maps  are  extant  on  which  the 
circular  outlines  are  represented  and  even  the  center  of  the  basin 
indicated.  As  stated  under  the  heading  Geologic  Structure,  the  writers 
considered  themselves  fairly  successful  in  determining  the  shape  and 
depth  of  the  Carthage  trough.  Fortunately  for  those  wishing  to  develop 
coal  mines,  this  trough  seems  to  be  comparatively  shallow  and  with 
a nearly  flat  bottom.  This  means  that  the  coal  beds,  as  well  as  the 
associated  rocks  are  but  slightly  disturbed  by  folds  and  faults  and 
consequently  that  mining  conditions,  even  at  a depth  are  fairly  good. 
The  shallowness  of  the  trough  also  means  that  much  more  of  the  coal 
is  accessible  than  would  be  the  case  were  the  dips  steep  and  regular 
from  the  rim  to  the  axial  line  and  consequently  much  more  of  the 
coal  is  within  mining  distance  of  the  surface  than  otherwise  would  be  the 
case. 

The  questions  which  the  operator  or  the  prospective  operator  wishes 
to  have  answered  are  these : 


THE  DEEP  EIVEE  COAL  FIELD 


77 


(1)  How  deep  can  successful  mining  be  carried?  (2)  How  far  will 
one  have  to  go  from  the  outcrop  to  reach  this  depth?  (3)  Does  the  coal 
bed  hold  a workable  thickness  as  far  as  it  is  within  mining  distance  of 
the  surface? 

The  first  is  an  engineering  question  and  can  be  answered  better 
by  a mining  engineer  of  experience  than  by  a geologist.  Nevertheless 
certain  things  are  apparent  in  the  mines  already  in  operation  which 
may  throw  some  light  on  the  possibility  of  conducting  deeper  operations 
farther  within  the  trough.  In  the  first  place  the  black  band  forming  the 
parting  between  the  two  benches  of  the  coal  bed  in  the  Cumnock  mine 
makes  an  excellent  floor  that  will  not  heave  under  pressure  from  the 
pillars.  Also  the  roof  is  excellent,  doubtless  being  able,  when  properly 
supported  to  withstand  the  load  of  many  hundreds  if  not  thousands  of 
feet  of  strata.  The  question  of  the  depth  to  which  mining  can  be 
carried  in  this  trough  is  largely  one  of  cost ; it  seems  probable,  however, 
that  mining  can  be  carried  to  a depth  of  2,000  feet,  without  great 
difficulty.  The  writers  have  based  their  conclusions  largely  upon  this 
assumption.  If  it  proves  to  be  erroneous,  some  reduction  will  have 
to  be  made  in  the  estimated  tonnage  of  coal  available. 

The  determination  of  the  location  of  the  points  at  which  the  coal 
reaches  a depth  of  2,000  feet  is  based  largely  upon  cross-sections  made 
up  from  observed  dips  along  the  line  of  the  section.  As  surface 
observations  on  the  dip  of  the  beds  are  not  entirely  reliable,  owing  to 
the  lack  of  distinctive  bedding  planes  in  the  more  massive  rocks  and  to 
the  disturbed  condition  of  the  rocks  in  the  presence  of  dikes,  the 
determination  of  the  true  dip  is  very  difficult  indeed.  Cross-sections 
constructed  under  such  conditions  must  be  regarded  as  provisional  only 
and  to  be  replaced  as  soon  as  more  reliable  data  are  available. 

Another  factor  that  must  be  taken  into  account  in  determining 
the  extent  of  workable  coal  within  the  trough  is  the  probability  that 
the  coal  bed  thins  southeastward  in  conformity  with  the  thinning 
noticed  on  the  outcrop.  Judging  by  the  facts  at  present  available,  one 
is  justified  in  the  conclusion  that  the  coal  bed  does  not  retain  a workable 
thickness  to  the  southeast  beyond  the  old  prospects  near  the  Mclver 
homestead,  east  of  the  Deep  River  fault.  He  is  also  justified  in 
assuming  that  the  bed  is  not  workable  much  beyond  Haw  Branch.  Of 
course  no  one  knows  whether  the  line  marking  the  limit  of  workability 
in  the  interior  of  the  trough  is  straight  between  these  two  points,  or 
whether  it  pursues  a circuitous  course.  In  the  absence  of  evidence 
to  the  contrary,  it  is  reasonable  to  assume  the  simpler  condition  rather 
than  a more  complicated  one,  therefore,  one  is  justified  in  assuming 
that  this  line  is  nearly  straight  between  the  points  specified  above,  and 
the  conclusions  arrived  at  by  the  writers  are  based  accordingly. 


78 


THE  DEEP  RIVER  COAL  FIELD 


An  estimate  of  the  tonnage  of  coal  available,  based  on  such  data 
is  of  course  very  inaccurate,  but  it  has  a certain  value,  as  being  under 
present  conditions,  the  best  guess  that  can  be  made,  but  it  should  be 
remembered  that  it  is  only  a guess.  In  making  this  guess  or  estimate, 
great  reliance  was  placed  on  the  section  along  the  Sanford-Cumnoek 
road  for  a distance  of  about  three  miles  from  the  village  of  Cumnock. 
On  this  section  the  writers  bad  as  a basis  the  data  from  the  Cumnock 
mine,  which  shows  the  coal  at  a depth  of  ^ about  600  feet  below  the 
surface,  and  the  log  of  drill-hole  Ho.  3,  which  recorded  the  bed  at  a 
depth  of  a little  more  than  900  feet  below  the  surface.  From  bore- 
hole Ho.  3 southward  the  section  was  based  solely  upon  dips  measured 
at  the  surface,  and  as  these  are  generally  slight  and  directed  to  various 
points  of  the  compass,  the  coal  bed  descends  very  slowly  toward  the 
south  and  it  is  estimated  that  at  a distance  of  3%  miles  from  the 
outcrop,  it  is  only  about  2,000  feet  below  the  surface. 

Similar  sections  have  been  constructed  from  the  south  end  of  this 
section  to  Gulf  and  to  Carbonton,  and  the  sections  have  been  made  to 
harmonize  at  their  common  meeting  point.  The  points  on  these  sections 
at  which  the  coal  is  estimated  to  be  at  a depth  of  2,000  feet  have  been 
connected  on  the  map  by  the  line  Y Z,  but  in  using  this  line  it  should 
be  remembered  that  its  position  is  only  vaguely  determined  and  that 
in  reality  its  place  may  be  changed  considerably  when  deep  drilling 
has  been  done.  In  the  meantime  this  line  is  intended  to  mark  the 
lower  limit  of  workable  coal  as  indicated  by  all  of  the  evidence  available 
at  the  present  time. 

All  territory  lying  between  the  line  Y Z and  the  outcrop  of  the 
coal  bed  and  extending  from  the  Deep  River  fault  to  the  Gardner  mine 
near  Haw  Branch  is  regarded  provisionally  as  coal  territory,  in  which 
the  coal  is  accessible,  providing  mining  can  he  carried  to  a depth  of 
2,000  feet.  The  area  included  within  the  lines  mentioned  above  is 
about  25  square  miles,  and  it  seems  reasonable  to  assume  that  the 
coal  bed  throughout  this  territory  averages  at  least  3 feet  in  thickness 
of  recoverable  coal.  The  weight  of  coal  necessarily  depends  upon  its 
specific  gravity,  and  it  is  assumed  that  the  Deep  River  coal  has  a 
specific  gravity  of  about  1.3.  This  is  an  assumed  figure,  as  no  specific 
gravity  determinations  of  the  coal,  as  far  as  the  writers  are  aware, 
have  been  made,  hut  it  is  based  on  many  determinations  of  the  specific 
gravity  of  various  coals  of  the  country.  As  the  weight  of  a cubic  foot 
of  water  weighs  62.5  pounds,  and  the  weight  of  coal  is  1.3  times  that 
of  water,  it  follows  that  the  weight  of  a cubic  foot  of  coal,  as  it  lies 
in  the  ground,  is  62.5  by  1.3  = 81.25  pounds.  The  number  of  cubic 


THE  DEEP  EIVER  COAL  FIELD 


79 


feet  in  a coal  bed  1 foot  thick  and  one  acre  in  extent  is  208.7  by  208.7 
by  1 = 43,556  cubic  feet,  and  as  the  weight  of  one  cubic  foot  is  81.25 
pounds  the  weight  of  the  whole  is  43,556  by  81.25  = 3,538,925  pounds 
or  roughly  1,770  short  tons.  If  the  coal  bed  is  3 feet  thick  then  the 
tonnage  per  acre  would  be  1,770  by  3 = 5,310  tons.  If  the  territory 
underlain  by  a 3-foot  bed  is  25  square  miles  or  16,000  acres,  then  the 
total  coal  in  the  ground  was  originally  5,310  by  16,000  = 84,960,000 
short  tons. 

The  figures  given  above  are  supposed  to  represent  the  total  coal  in 
the  coal  bed,  but  not  the  amount  that  could  be  recovered  in  actual 
mining.  In  order  to  determine  the  amount  that  actually  could  be 
recovered,  it  is  necessary  to  allow  for  pillars  that  cannot  be  removed, 
for  partings  that  may  come  into  the  bed  and  replace  good  coal,  and 
for  the  amount  of  coal  lost  by  dikes  and  faults  cutting  the  coal  bed. 
As  there  are  little  or  no  data  available  in  this  field  regarding  the 
factors  mentioned  above,  an  accurate  estimate  is  not  possible,  but,  if 
the  mining  conditions,  as  developed  in  the  Cumnock  mine,  hold 
throughout  the  territory  included  between  the  outcrop  of  the  coal  bed 
and  the  line  Y Z it  is  probable  that  80  per  cent  of  the  coal  in  the  bed 
can  be  recovered.  Eighty  per  cent  of  84,960,000  tons  is  67,968,000 
tons  or  the  estimated  tonnage  of  recoverable  coal  in  this  field  west  of 
the  Deep  River  fault.  The  amount  of  coal  east  of  this  fault  cannot 
be  estimated  at  the  present  time,  for  there  is  little  or  no  positive 
evidence,  that  the  coal  is  more  than  2 feet  thick  in  any  part  of  this 
territory  and  a bed  of  this  thickness  can  hardly  be  considered  workable 
at  a depth  under  present  conditions.  If  drilling  in  the  territory  east 
of  the  fault  should  reveal  a coal  bed  more  than  2 feet  in  thickness, 
it  would  be  worth  considering  in  a commercial  way,  but  until  drilling 
is  done  it  is  useless  to  speculate  whether  or  not  there  is  a supply  of 
workable  coal  east  of  this  fault. 

Similarly  there  may  be  workable  coal  southwest  of  Haw  Branch, 
but  the  surface  indications  are  not  favorable  and  additional  data  can 
be  obtained  only  by  prospecting  with  pick  and  shovel  or  preferably  with 
a core  drill. 

Character  of  the  Coal 

The  coal  of  the  upper  bench  of  the  Cumnock  bed  is  known  only  in  the 
Cumnock  and  Carolina  mines  where  it  is  a jet  black  coal  with  few, 
if  any,  dull  bands.  In  other  parts  of  the  field,  particularly  toward  the 
southwest,  the  coal  bed  is  broken  up  by  layers  of  shale  which  detract 
greatly  from  its  value.  In  the  mine  mentioned  above  the  coal  is  fairly 
homogeneous  in  texture  and  quality  throughout. 


80 


THE  DEEP  RIVER  COAL  FIELD 


Cleavage  is  highly  developed  in  the  coal,  the  principal  cleavage 
planes  being  at  right  angles  to  the  strike  of  the  bed.  The  cleavage  is 
so  marked  that,  on  a face  of  coal  parallel  with  these  planes,  the  coal 
cleaves  off  in  thin  layers,  ranging  in  thickness  from  about  one-eighth 
to  one-half  inch.  One  can,  with  the  hand,  peel  these  thin  laminae  off 
the  face  to  an  almost  indefinite  depth.  Haturally  a coal  so  highly 
cleaved  as  this  coal  is,  will  produce  a very  small  percentage  of  lump 
when  mined  and  hence  the  coal  in  its  raw  state  is  not  well  adapted  to 
domestic  use.  In  the  run-of-mine  form  there  are  few  fragments  larger 
than  one’s  hand,  and  even  fragments  of  this  size  are  liable  to  be  broken 
much  finer  in  handling  and  shipping. 

Yery  great  ignorance  prevails,  even  in  the  Deep  Diver  Field  itself, 
regarding  the  quality  of  the  coal  now  being  mined  there,  and  outside  the 
limits  of  the  field,  few  persons  know  anything  about  it.  The  writers 
have  been  assured  that  the  coal  is  worthless;  that  locomotive  tests 
have  been  attempted  in  times  past  with  this  coal,  but  that  it  was  so 
poor  that  the  locomotive  went  “dead”  on  the  road,  the  coal  being  of 
such  a quality  that  it  would  not  produce  enough  steam  to  run  a light 
engine.  The  writers  do  not  question  the  reports  that  such  tests  were 
made,  but  they  do  maintain  that,  if  such  tests  were  made  and  resulted 
as  disastrously  as  reported,  the  material  used  was  not  the  best  nor 
even  the  average  coal  of  the  upper  bench,  or  if  it  came  from  this  bed 
it  was  outcrop  coal  which  had  weathered  to  such  an  extent  that  it  had 
lost  most  if  not  all  of  its  heating  value.  It  is  possible,  of  course,  that 
these  tests  were  made  on  coal  from  the  lower  bench,  and,  if  that  were 
the  case,  the  failure  could  be  easily  explained  for  the  heating  value  of 
this  coal  compared  with  that  of  coal  from  the  upper  bench,  is  as 
10,400  to  13,100,  or  only  76  per  cent  as  efficient  in  the  production 
of  heat. 

For  the  seven  years  prior  to  1922  the  Cumnock  mine  has  been  owned 
and  operated  by  the  FTorfolk  Southern  Railroad  Company,  and  prac- 
tically the  entire  output  of  the  mine  has  been  used  by  that  company 
for  locomotive  fuel  and  for  stationary  steam  plants  along  the  right- 
of-way.  If  the  coal  were  as  poor  as  some  have  believed,  it  could  not 
have  been  used  in  this  manner. 

In  order  to  determine  the  true  value  of  the  coal,  the  writers  cut  one 
sample  in  the  mine  of  the  Carolina  Coal  Company  for  analysis  aud 
Mr.  J.  J.  Forbes  of  the  United  States  Bureau  of  Mines  cut  several 
samples  in  both  the  Carolina  and  the  Cumnock  mine  for  the  same 
purpose.  The  results  of  the  analysis  of  these  samples  in  the  Pittsburgh 
laboratory  of  the  Bureau  of  Mines*  are  given  in  the  following  table, 
together  with  the  analyses  of  other  coals  of  the  Appalachian  region 


THE  DEEP  RIVER  COAL  FIELD 


81 


with,  which  the  Deep  River  coal  may  come  in  competition.  Each 
analysis,  as  a matter  of  convenience,  for  various  users,  is  presented  in 
three  forms,  marked  A,  B,  and  C.  Form  A represents  the  coal  in  the 
same  condition  as  it  was  in  the  mine  before  the  sample  was  cut  for 
sampling,  the  coal  sent  to  the  laboratory,  was  sealed  air-tight  in 
a galvanized-iron  can  so  that  it  reached  the  laboratory  without  taking 
on  or  giving  off  moisture ; form  B represents  theoretically  dry  coal ; 
and  form  C represents  the  theoretical  condition  of  the  coal  after  all 
moisture  and  ash  have  been  eliminated.  The  percentage  given  in  form 
A are  the  ones  that  should  he  used  in  the  comparison  of  coals  and  in 
the  study  of  a coal  with  respect  to  its  adaptability  to  certain  uses,  for 
this  form  more  nearly  represents  the  coal  that  is  actually  shipped  and 
fed  into  the  furnace  than  are  those  given  in  either  form  B or  form  C. 
Form  B is  the  one  most  used  by  mechanical  engineers,  because  it  is 
a more  stable  form  of  fuel  than  is  form  A,  and  the  mechanical  engineer 
is  more  concerned  in  the  testing  of  apparatus  than  he  is  in  testing 
coal.  Form  C is  used  only  when  it  is  desirable  to  compare  the  coal 
substance  itself  of  one  coal  with  another,  regardless  of  impurities,  or 
when  the  relation  of  the  volatile  matter  to  the  fixed  carbon  is  the  all 
essential  consideration.  The  forms  B and  C are  adapted  for  special 
purposes  only  and  should  not  he  used  by  the  ordinary  operator, 
purchaser,  or  consumer  of  the  coal. 


Geol. — 6 


ANALYSES  OF  COAL  SAMPLES  FROM  THE  DEEP  RIVER  COAL  FIELD 


82 


THE  DEEP  RIVER  COAL  FIELD 


THE  DEEP  RIVER  COAL  FIELD 


83 


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ANALYSES  OF  COAL  SAMPLES  FROM  OTHER  FIELDS,  WITH  WHICH  THE  DEEP  RIVER  COAL  MAY  HAVE  TO  COMPETE 


84 


THE  DEEP  RIVER  COAL  FIELD 


THE  DEEP  RIVER  COAL  FIELD 


85 


In  using  the  figures  given  in  the  table  of  analyses  it  should  be 
remembered  that  the  sampler  is  much  more  careful  in  excluding 
impurities  than  is  the  miner  or  even  the  operator  in  time  of  great 
scarcity  of  coal,  and  consequently  the  coal  that  reached  the  market 
from  these  mines  is  liable  to  contain  much  more  ash  than  that  shown 
in  the  analysis  of  the  mine  samples. 

A comparison  of  results  obtained  on  mine  samples  and  on  railroad 
car  samples  shows  that  on  the  average  the  ash  in  the  car  sample  may 
be  from  30  to  50  per  cent  greater  than  it  is  in  the  mine  sample. 
Thus  coal  which  shows  6 per  cent  ash  in  the  mine  sample  is  likely 
in  the  car  sample  to  run  from  7.8  per  cent  to  9 per  cent,  but  if  the 
increase  exceeds  50  per  cent,  it  indicates  gross  carelessness  in  mining  the 
coal  or  preparing  it  for  the  market. 

The  composition  of  the  mine  sample  may  be  regarded  as  the  ideal 
toward  which  the  commercial  coal  of  the  mine  approaches  more  and 
more  closely  as  better  methods  and  more  care  is  exercised  in  min- 
ing, and  commercial  coal  will  agree  with  the  mine  sample  when 
the  best  methods  are  used  and  every  employee  cooperates  with  the 
management  in  excluding  impurities  from  the  output  of  the  mine. 

As  the  most  important  point  in  the  consideration  of  the  value  of  a 
coal  for  ordinary  purposes  is  its  heat-producing  power,  the  column 
headed  B.  t.  u.1  in  the  table  of  analysis  is  worthy  of  most  careful 
consideration.  As  a direct  comparison  of  figures  is  not  easy  to  make,  the 
graph,  shown  in  Big.  6,  has  been  prepared  to  show  the  comparative 
heating  values  of  the  coals  listed  in  the  table  of  analyses.  It  is  apparent 
from  the  graph  that  Cumnock  coal  is  somewhat  inferior  in  heating 
value  to  the  best  Pocahontas  and  Hew  River  coals,  and  that  it  is  about 
the  same  as  the  coal  mined  at  Dante,  Toms  Creek,  and  Big  Stone  Gap, 
Virginia,  and  Oliver  Springs  and  Jellico,  Tennessee,  but  is  considerably 
better  than  the  poorer  coals  mined  in  most  of  these  districts. 

The  table  of  analyses  shows  that  the  Cumnock  coal  is  relatively 
high  in  sulphur,  averaging  in  eight  mine  samples,  2.2  per  cent,  as 
against  an  average  of  1.1  per  cent  in  the  other  coals  listed  in  the  table. 
The  difference  between  1.1  and  2.2  is  not  serious,  unless  the  coal  were 
used  for  the  manufacture  of  metallurgical  coke,  where  difference  of 
1.1  per  cent  would  be  a rather  important  matter.  In  steam-raising  the 
percentage  of  sulphur  in  the  Cumnock  coal  will  probably  have  little 

U3.  t.  u.  is  an  abbreviation  of  the  term  British  thermal  unit.  This  unit  is  the  one 
by  which  heat  is  generally  measured  and  expressed  in  English  speaking  countries.  The 
heat-producing  value  of  a coal  is  determined  in  the  laboratory  by  exploding  a small 
amount  of  coal  within  a steel  bomb  and  carefully  measuring,  by  a delicately  graduated 
thermometer  the  increase  in  temperature.  The  amount  of  heat  thus  generated  is  ex- 
pressed in  British  thermal  units,  one  of  these  units  being  the  amount  of  heat  required  to 
raise  one  pound  of  water  one  degree  Fahrenheit,  the  water  being  at  the  temperature  of 
maximum  density,  39.1  degrees  F. 


86 


THE  DEEP  RIVER  COAL  FIELD 


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or  no  effect,  except  that  the  sulphur  will  tend  to  corrode  the  grate  bars 
more  rapidly  than  pure  coal.  It  should  he  remembered  by  operators, 
however,  that  the  sulphur  in  the  coal  as  shipped  to  market  is  liable  to 
he  much  greater  than  that  shown  in  the  mine  samples.  This  is  an 
imminent  danger,  for  in  places  the  coal  contains  many  “sulphur”  balls 
from  1 inch  to  2 or  more  inches  in  diameter.  In  mine  sampling  these 
nodules  of  pyrite  were  excluded  from  the  samples  on  the  theory  that  in 
actual  mining  it  is  possible  to  remove  them  if  the  coal  is  properly 
hand-picked,  and  no  careful  operator  who  is  at  all  mindful  of  the 
reputation  of  his  output,  will  allow  such  material  to  remain  in  the 
commercial  coal. 

Tests  by  the  Bureau  of  Mines 

The  Deep  River  coal  is  generally  regarded  as  a coking  coal,  hut 
up  to  the  time  of  the  present  examination,  no  reliable  test  of  its  coking 
properties  had  been  made,  or  if  made,  the  winters  were  not  aware  of 
the  fact.  The  coal  has  been  noted  since  its  earliest  exploitation  as  a 
fine  smithing  coal  and  this  in  itself  is  an  indication  of  its  coking 
quality,  as  one  of  the  prime  requisites  of  a smithing  coal  is  that  it 
will  coke  and  thus  make  a “hollow”  fire. 

At  the  request  of  Col.  Joseph  Hyde  Pratt,  State  Geologist,  the 
United  States  Bureau  of  Mines  has  recently  made  tests  of  the  coking 
quality  of  the  Deep  River  coal  and  of  its  adaptability  to  washing  as  a 
means  of  reducing  the  sulphur  and  ash  so  as  to  make  it  suitable  for 
the  manufacture  of  metallurgical  coke.  Through  the  courtesy  of  the 


THE  DEEP  EIVEE  COAL  FIELD 


87 


Director  of  tlie  Bureau  of  Mines  the  essential  features  of  these  tests  are 
given  herewith. 

A large  sample  of  washed  coal  from  the  top  bench  in  the  Cumnock 
mine  was  tested  at  the  Experiment  Station  of  the  United  States  Bureau 
of  Mines  at  Pittsburgh,  Pennsylvania,  for  its  coking  properties  and  for 
the  by-products  w’hich  it  would  yield  in  the  operation.  The  sample 
of  washed  coal  which  was  to  he  tested  had  the  following  composition : 


PEOXIMATE  AND  ULTIMATE  ANALYSES  OF  WASHED  COAL  AND  COKE 


Moisture 
Volatile  matter 
Fixed  carbon 
Asli 

Hydrogen 
Carbon 
Nitrogen 
Oxygen  . 
Sulphur  . 

B.  t.  u. 


Coal 

Per  Cent 

1.0 

33.0 
59.6 
6.4 

5.2 
78.9 
2.1 
5.8 
1.6 
14220 


Coke 
Per  Cent 
0.5 
3.8 

87.2 
8.5 

1.2 

86.0 
2.0 

1.0 

1.3 
13350 


The  results  of  the  laboratory  coking  tests  on  the  washed  coal  is  as 
follows : 

Final  coking  temperatures  ....  775°  to  800°  C. 

Weight  of  charge 15  pounds. 

Coke  yield 75  per  cent  of  charge. 

Gas  yield 8.000  cu.  ft.  per  ton  of  coal. 

Ammonium  sulphate 23  pounds  per  ton  of  coal. 

Tar  (dehydrated) 13.9  per  cent  of  coal  charged 

or  22  gallons  per  ton. 

The  report  of  the  Bureau  of  Mines  on  this  test  is  as  follows : 

“The  by-product  yield  of  this  coal  is  entirely  satisfactory  and  compares 
favorably  with  yields  from  Freeport,  Pa.  coal.  It  is  felt  that  with  a full 
cooking  temperature  (950°C.)  and  18  hours  time,  it  would  be  reasonable  to 
expect  a 70  per  cent  yield  of  matallurgical  coke,  10,000  to  12.000  cubic  feet 
of  good  gas,  11  gallons  of  tar,  and  25  to  27  pounds  of  ammonium  sulphate. 
In  general,  the  coke,  as  far  as  it  can  be  judged  by  a laboratory  scale  test  is  of 
very  good  quality  fully  equal  in  all  respects  to  Freeport  or  Pittsburg  cokes. 
The  sulphur  in  the  coke  is  somewhat  high (1.3  per  cent),  but  this  could  be 
cut  down  by  admixture  of  a low-sulphur  steam  coal.  Such  a mixture  of  coal  is 
now  considered  to  be  good  by-product  practice.” 

This  test  seems  to  establish  the  coking  quality  of  the  Deep  River 
coal  and  also  the  fact  that  even  by  washing,  the  sulphur  is  too  high 
to  yield  a metallurgical  coke  without  the  admixture  of  a coal  containing 
less  sulphur.  As  there  is  probably  little  or  no  demand  for  this  kind  of 


88 


THE  DEEP  EIVEE  COAL  FIELD 


coke  in  North  Carolina,  the  relatively  high  percentage  of  sulphur  is  not 
an  important  matter.  It  seems  probable  that  the  best  market  in  the 
State  for  coke  is  for  domestic  use  as  a substitute  for  anthracite,  and 
for  this  use  the  sulphur  is  not  excessive.  In  an  agricultural  country, 
such  as  central  North  Carolina,  it  is  probable  that  the  ammonium 
sulphate  is  a very  important,  if  not  the  most  important,  by-product  of  the 
coking  process.  In  using  the  figures  given  in  such  a report,  it  should  be 
understood  that  the  results  of  a general  test  are  significant  only  in  sug- 
gesting what  may  be  secured  in  actual  practice,  but  the  actual  yield  of 
any  by-product  depends  largely  upon  the  method  used,  and  the  method 
best  suited  to  produce  a large  quantity  of  a certain  constituent  is  not 
the  one  best  suited  to  obtain  a large  yield  of  another  constituent. 

The  results  of  the  Bureau  of  Mines  test  show  that,  if  the  coal  is 
coked  in  by-product  ovens,  a good  quality  of  coke  may  he  secured  for 
domestic  or  manufacturing  purposes,  a normal  amount  of  gas,  a rather 
large  yield  of  ammonium  sulphate  for  the  cotton  and  tobacco  fields, 
and  a medium  amount  of  tar. 

As  the  two  coal  beds  in  the  vicinity  of  Cumnock  are  only  18  inches 
apart,  they  may  easily  be  regarded  as  two  benches  of  a single  coal  bed, 
but  there  is  no  advantage  in  so  considering  them  unless  the  coal  con- 
tained in  the  lower  bench,  as  well  as  the  black  band  (iron  carbonate) 
between  them,  can  be  utilized.  As  shown  by  the  analyses  of  the  coal 
from  the  lower  bench  that  are  given  in  the  table  (p.  83),  the  coal 
in  the  raw  state  contains  too  much  ash  to  be  salable  in  competition 
with  better  coals,  therefore  if  it  is  to  be  utilized,  some  way  of  improv- 
ing its  condition  must  be  devised.  In  order  to  determine  the  possibility 
of  reducing,  by  washing,  the  percentage  of  ash  in  the  lower  bench  from 
about  30  per  cent  to  6 or  8 per  cent,  a washing  test  was  made  by  the 
United  States  Bureau  of  Mines.  In  order  to  make  a thorough  test 
about  1,150  pounds  of  coal  was  sent  to  the  Bureau  of  Mines  testing 
laboratory  at  Urbana,  Illinois,  and  elaborate  float-and-sink  test  were 
made  with  liquids  ranging  in  specific  gravity  from  1.3  to  1.8.  Tests 
were  also  made  in  washing  the  coal  in  jigs  and  on  tables,  but  without 
very  satisfactory  results. 

The  conclusions  arrived  at  by  the  Bureau  of  Mines  experts  are 
as  follows : 

The  sample  of  coal  received  at  the  laboratory  representing  the  bottom  bench 
of  the  Cumnock  bed  from  the  Farmville  (Carolina  Coal  Company’s)  mine, 
consists  very  largely  of  bony  coal  and  carbonaceous  shale.  Only  a small 
amount  of  coal  low  in  ash  content  is  present.  It  is,  therefore,  impossible  to  treat 
this  coal  successfully  by  the  usual  coal-washing  methods  to  secure  a reason- 
able yield  of  coal  as  low  in  ash  content  as  the  coal  of  the  top  bench  (S  to  10 
per  cent,  of  the  bed ) . The  treatment  of  this  coal  at  % inch  minimum  size  on 


THE  DEEP  RIVER  COAL  FIELD 


89 


either  jigs  or  tables  would  probably  yield  50  to  70  per  cent  of  washed  coal 
with  an  ash  content  in  the  neighborhood  of  24  per  cent. 

As  stated  before,  this  test  shows  that  washing  will  probably  not 
improve  the  coal  of  the  lower  bench  sufficiently  to  justify  the  erection 
of  a washery  and  therefore  some  other  method  must  be  sought,  if  this 
bench  of  the  coal  is  to  be  utilized  at  the  same  time  that  the  upper 
bench  is  being  mined. 

As  the  sulphur  content  of  the  upper  bench  of  the  Cumnock  coal  bed 
is  too  great  for  the  manufacture  of  metallurgical  coke,  a washing  test  of 
this  coal  was  also  made  by  the  United  States  Bureau  of  Mines  at  its 
Urbana,  Illinois  plant  to  see  if  it  were  possible  by  ordinary  washing 
methods  to  materially  reduce  this  element.  Elaborate  tests  were  made 
by  float-and-sink  methods,  by  washing  in  jigs,  and  by  washing  on  tables. 

The  coal  to  be  tested  was  crushed  to  different  sizes  and  subjected 
to  a float-and-sink  test  on  liquids  of  various  densities  with  the  result 
that  it  appears  to  be  entirely  feasible  to  reduce  both  the  sulphur  and 
ash  by  washing  processes.  The  float-and-sink  test  showed  that  with  a 
solution  whose  specific  gravity  is  1.5  the  ash  could  be  reduced  from 
12.7  to  6.5  per  cent;  the  sulphur  could  be  reduced  from  2.32  to  1.76 
per  cent;  with  a consequent  loss  of  the  sample  tested  of  9.4  per  cent. 

After  this  preliminary  test  had  been  made  the  raw  coal  was  washed 
in  a jig.  This  test  yielded  87.6  per  cent  of  washed  coal,  having  7.1 
per  cent  of  ash  and  1.85  per  cent  of  sulphur.  The  results  of  this  test 
are  very  satisfactory,  as  far  as  the  ash  is  concerned,  but  rather  disap- 
pointing as  the  percentage  of  sulphur  was  not  materially  reduced.  A 
table  test  showed  a yield  of  washed  coal  of  87.6  per  cent,  having  an  ash 
content  of  7.1  per  cent,  and  a sulphur  content  of  1.79  per  cent.  A table 
test  of  coal  crushed  finer  than  that  noted  above,  yielded  90.0  per  cent 
of  washed  coal,  having  6.8  per  cent  of  ash  and  1.82  per  cent  of 
sulphur. 

As  these  various  tests  agree  very  closely,  it  may  be  said  that,  as  far 
as  a single  test  on  a small  scale  will  determine,  the  coal  from  the  upper 
bench  of  the  Cumnock  bed,  if  subjected  to  washing  in  a jig,  would  have 
its  percentage  of  ash  materially  reduced,  but  that,  as  far  as  the 
sulphur  is  concerned,  the  results  hardly  justify  the  expense  of  the 
operation. 

The  failure  to  greatly  reduce  the  content  of  sulphur  is  explained  as 
follows : 

The  general  sample  representing  the  entire  lot  of  coal  contained  1.52  per 
cent  of  pyritic  sulphur  and  0.S0  per  cent  of  organic  sulphur.  The  total  sulphur 
content  amounted  to  2.32  per  cent,  of  which  34.5  per  cent  was  present  as 
organic  sulphur  and  65.5  per  cent  as  pyritic  sulphur.  Sulphate  sulphur  was 
not  determined  as  the  analysis  made  at  the  Pittsburg  station  of  the  mine 


90 


THE  DEEP  RIVER  COAL  FIELD 


samples  showed  a maximum  value  of  only  0.026  per  cent.  . . . This  con- 

dition is  favorable  for  a good  sulphur  reduction,  but  it  is  counterbalanced  by 
the  finely  disseminated  nature  of  the  pyritic  sulphur  present  in  the  coal. 

Ash  reduction  by  Trent  process. — A final  attempt  to  reduce  tlic 
percentage  of  ash.  in  the  coal  of  the  lower  bench  of  the  Cumnock  coal 
bed  was  made  by  the  Trent  process — a patented  process  which,  in 
certain  coals,  will  reduce  the  ash  very  materially  indeed.  The  test  was 
made  at  the  works  of  the  company  in  Alexandria,  Virginia. 

The  Trent  process  for  reducing  ash  in  coal,  consists  in  dry  pulveriz- 
ing the  coal  so  that  it  will  go  through  100-mesh  sieve;  wetting  of  the 
pulverized  material  with  water  from  the  tap;  and  then  the  addition  of 
a small  percentage  of  standard  ISTavy  fuel  oil.  The  oil  tends  to  unite 
with  the  carbon,  freeing  the  earthy  matter  which  settles  to  the  bottom. 

The  sample  to  be  tested,  which  consisted  of  run-of-mine  coal  from 
the  lower  bench  in  the  Carolina  mine,  had  the  following  composition : 
moisture,  1.4;  volatile  matter  29.4;  fixed  carbon  42.0;  ash,  27.2.  The 
so-called  “amalgam”  resulting  from  the  combination  of  the  oil  and 
carbon  had  the  following  composition : volatile  matter,  48.5 ; fixed 
carbon,  38.1;  ash,  13.4.  If  this  amalgam  is  then  subjected  to  low 
temperature  distillation  until  the  oil  that  has  been  added  is  driven  off, 
the  resultant  purified  coal  contains  17.1  per  cent  of  ash. 

If  the  coal  were  treated  by  this  process,  the  result  would  be  the 
so-called  amalgam  which  contains  about  21.6  per  cent  of  fuel  oil  in 
addition  to  the  finely  divided  carbon  and  ash,  or  if  the  oil  were  distilled 
it  would  leave  only  the  finely  divided  carbon  and  ash.  In  either  form 
the  product  can  be  used  as  a fuel — if  in  the  amalgam  form  with  a 
content  of  ash  of  13.4  per  cent  and  if  in  the  form  of  dry  purified  coal 
with  an  ash  content  of  17.1  per  cent. 

The  reduction  of  the  ash  by  this  process  is  rather  disappointing 
and  is  said  to  be  due  to  the  fact  that  the  earthy  material  is  present  in 
a very  finely  divided  condition  and  this  means  that  to  reach  the  carbon 
itself,  the  crushing  would  have  to  be  possibly  to  200  mesh  which  would  be 
quite  expensive. 

There  is  no  question  about  the  effectiveness  of  this  process,  but  in 
certain  cases  the  reduction  in  the  ash  is  not  nearly  so  marked  as  in 
others.  The  operator  considering  this  process  should  calculate  closely 
the  cost  of  separating  this  bench  of  coal  from  the  upper  bench,  its 
crushing  down  to  the  required  degree  of  fineness  and  finally  the  market- 
ing of  the  product,  either  in  the  form  of  oil-amalgam,  powdered  fuel, 
or  briquettes  made  from  the  powdered  material. 


THE  DEEP  RIVER  COAL  FIELD 


91 


POSSIBILITIES  OF  PETROLEUM  IN  THE  DEEP  RIVER  FIELD 

Much  speculation  has  been  indulged  in  here  as  well  as  in  other 
States  crossed  by  the  belt  of  rocks  of  Triassic  age  as  to  the  possibility  of 
obtaining  oil  or  gas  from  the  sandstone  which  forms  such  a large 
proportion  of  their  bulk.  Many  reports  are  current  regarding  so-called 
oil  seeps  and  gas  is  supposed  to  bubble  up  through  the  water  in  many 
of  the  streams.  The  writers  examined  a number  of  these  localities 
supposed  to  show  signs  of  oil,  but  none  was  seen,  though  the  oxide  of 
iron  which  generally  forms  an  iridescent  scum  on  stagnant  water  was 
seen  at  a number  of  places.  Persons  finding  such  an  iridescent  scum 
on  water  may  easily  test  it  by  stirring  the  water  with  a stick.  If  the 
scum  can  be  drawn  out  and  stirred  into  whorls  without  breaking,  it  is 
probably  oil  of  some  kind,  but  if  it  is  brittle  and  breaks  when  stirred, 
it  is  oxide  of  iron  and  worthless. 

As  there  are  apparently  no  signs  of  petroleum  at  the  surface,  the 
next  step  in  the  investigation  is  to  study  the  rocks  of  tbe  region  to 
see  if  the  conditions,  which  by  long  experience  geologists  have  come 
to  regard  as  essential,  are  present  or  not,  for  in  many  of  the  well  known 
oil  fields  there  were  absolutely  no  surface  indications  of  the  presence 
of  oil  or  gas  before  drilling  began.  In  conducting  the  geologic  study 
of  the  possibility  of  oil  pools  there  are  four  elements  that  enter  into 
the  problem.  These  are:  (1)  the  presence  of  rocks  of  such  a character 
that  they  may  have  served  as  the  place  of  origin  or  source  of  oil  or 
gas;  (2)  porous  sandstones  or  limestones  into  which  the  oil  when 
formed,  can  collect;  (3)  a geologic  structure  or  fold  of  such  a character 
that  it  will  trap  the  oil  and  gas  as  they  migrate  through  the  porous 
rock;  and  (4)  a nonporous  shale  or  clay  above  the  sandstone  to  seal  in 
its  oily  .contents  and  prevent  their  escape* 

(1)  As  petroleum  has  been  derived  largely,  if  not  wholly,  from 
organic  remains  which  were  buried  in  the  mud  or  sand  that  now  form 
the  country  rock,  it  will  be  necessary  to  find  a fairly  thick  formation 
which  contains  fossil  remains  in  abundance.  All  of  the  ISTewark  rocks 
of  the  Deep  River  Field  appear  to  have  been  laid  down  in  fresh  water 
or  on  the  land,  hence  they  do  not  contain  a marine  fauna  from  which 
the  oil  could  have  been  derived.  The  presence  of  beds  of  coal  and  some 
black  shale  are  indications  of  abundant  vegetal  growth,  but  in  all 
except  the  Cumnock  formation  the  materials  are  so  coarse  that  air 
could  easily  have  reached  the  enclosed  vegetal  matter  and  cause  its 
destruction.  The  black  shale  and  coal  of  the  Cumnock  formation  would 
probably  supply  some  material  for  the  formation  of  oil,  but  the  volume 
of  such  shale  and  coal  is  so  small  that  the  amount  of  oil  that  may  have 
been  produced  from  them  in  the  past  is  negligible.  It  is  true  that 


92 


THE  DEEP  RIVER  COAL  FIELD 


some  layers  of  the  shale  are  quite  rich  in  bituminous  material,  and 
that  at  one  time  there  was  a manufacturing  plant  in  operation  at 
Farmville  for  the  distillation  of  oil  from  the  shale  and  coal,  but,  as 
described  on  a previous  page,  the  Cumnock  formation  is  in  many  parts 
of  the  field  apparently  thin  and  in  places  is  apparently  replaced  by 
red  conglomerate,  and  consequently  the  volume  of  possible  oil-producing 
shale  is  small.  On  account  of  this  replacement  toward  the  southeast, 
the  part  of  the  field  most  promising,  as  a source  of  oil,  is  about  Cumnock 
and  Gulf  where  the  formation  is  thickest  and  contains  the  most  bitu- 
minous material.  But  here  erosion  has  cut  deeply  into  the  formation 
without  exposing  any  trace  of  the  coveted  substances. 

(2)  There  are  many  beds  of  porous  sandstone  in  the  Cumnock  forma- 
tion, where  it  is  well  developed,  that  might  serve  as  reservoirs  for 
oil  or  gas,  and  even  in  the  overlying  Sanford  formation  there  are 
coarse  brown  sandstones  that  might  serve  a similar  purpose,  if  other 
conditions  were  favorable. 

(3)  Wide  experience  of  petroleum  geologists  all  over  the  world  has 
demonstrated  that  about  90  per  cent  of  the  oil  is  found  in  anticlines 
or  arches  in  the  rocks,  hence  the  first  thing  the  oil  geologist  does  is 
to  look  for  such  structures.  As  stated  previously  there  are  few  known 
anticlines  in  this  field.  In  general  the  rocks  have  been  depressed  into 
basins  or  troughs  rather  than  raised  into  anticlines  or  arches.  Thus  the 
Carthage  and  the  Corinth  troughs  are  both  essentially  synclinal  in 
structure,  although  in  each  case  the  scycline  is  not  complete  because  of 
the  great  fault  along  the  southeast  side.  On  account  of  this  structure 
neither  basin  nor  trough  can  he  considered  a favorable  place  to  drill  for 
oil.  As  described  previously  these  troughs  are  united  by  a cross-anti- 
cline at  Colon,  but  this  fold  has  raised  the  formation  so  high  that  the 
Cumnock  formation  crops  out  at  the  surface  as  far  east  as  Colon,  hence 
there  are  scarcely  any  rocks  below  the  surface  on  this  anticline  that 
might  he  considered  as  sources  of  oil  or  gas.  Another  disturbing  factor 
in  this  anticline  is  the  possibility,  if  not  probability  that  it  is  broken 
along  its  crest,  by  a fault  which  follows  the  system  of  dikes  north  to 
Colon  and  there  turns  to  the  northwestward  to  the  margin  of  the 
field.  Altogether  the  Colon  cross-anticline  does  not  seem  promising 
from  a geological  point  of  view. 

In  referring  to  anticlines  as  the  most  favorable  rock  structures 
for  holding  accumulations  of  oil  or  gas,  it  must  he  understood  that  this 
statement  applies  only  to  rocks  that  are  saturated  with  water  and  that 
in  dry  rocks  the  oil  accumulates,  if  it  accumulates  at  all,  in  very  different 
places.  This  is  illustrated  by  Fig.  7,  which  is  supposed  to  he  a cross- 
section  representing  the  rocks  as  they  would  appear  in  the  side  of 


THE  DEEP  RIVER  COAL  FIELD 


93 


a deep  trench,  cutting  an  anticline  and  a syncline.  A B represents  a 
moderately  coarse  porous  sandstone  which  is  the  reservoir  rock.  C D 
is  the  overlying  impervious  shale  which  serves  as  a blanket  and  retains 
any  fluid  that  may  he  in  the  reservoir  rock.  As  water  is  heavier  than 
oil  and  as  both  of  these  substances  are  heavier  than  gas,  the  three  will 
arrange  themselves,  under  the  influence  of  gravity,  in  the  order  shown 
in  the  figure,  gas  at  the  top,  oil  next  lower  in  the  anticline,  and  then 
water  occupying  almost  all  of  the  synclinal  fold.  If  a well  is  drilled 
at  a it  will  encounter  gas;  at  b,  oil;  and  at  c,  water.  In  some  cases 
there  is  little  or  no  gas  and  then  the  oil  is  forced  into  the  crown  of  the 
arch  and  a well  drilled  at  a would  strike  oil. 

If  the  rocks  are  not  saturated  with  water,  then  there  is  no  force 
to  drive  the  hydrocarbons  into  the  anticline,  and,  under  the  pull  of 
gravity,  the  oil  would  tend  to  migrate  toward  the  bottom  of  the  syncline 
at  E.  Such  cases  are  seldom  met  with,  but  some  of  the  oil  pools  in 
western  Pennsylvania  are  in  dry  rocks  and  the  oil,  though  much  dis- 
seminated in  the  reservoir  rocks,  appears  to  be  slowly  migrating  down- 
ward, but  is  arrested  locally  by  denser  portions  of  the  sandstone  and 
small  pools  on  the  limbs  of  the  syncline  are  of  common  occurrence.  If 
the  oil  is  not  trapped  by  barriers  of  dense  rock,  it  finally  reached  the 
bottom  of  the  syncline,  but  a pool  in  such  a situation  is  rare  indeed. 

(4)  The  different  beds  of  the  formations  in  this  field  are  not  well 
enough  known  to  enable  one  to  say  positively  that  any  given  porous 
sandstone  is  overlain  by  a nonporous  shale,  but  generally  the  succession 
of  shale  and  sandstone  is  the  rule  and  it  is  probable  that  most  porous 
sandstones  have  a shale  cap.  So  far  as  this  element  of  the  problem 
is  concerned,  it  may  be  taken  for  granted  that  it  is  favorable. 

In  addition  to  the  elements  of  the  oil  problem  enumerated  above, 
geologists  are  now  coming  to  acknowledge  a fifth  element  in  the  degree 
of  metamorphism  which  has  affected  the  rocks  and  which  is  apparently 
all  important  in  determining  in  advance  of  drilling  or  even  geologic 
investigation  whether  or  not  there  is  a possibility  of  obtaining  oil  if  a 
well  were  drilled.  Metamorphism  means  change  and  changes  in  the 


94 


THE  DEEP  RIVEK  COAT  FIELD 


rocks  are  induced  by  crustal  movements,  probably  accompanied  by  the 
development  of  sensible  heat.  When  rocks  have  been  squeezed  to  such 
an  extent  as  to  produce  heat,  their  condition  and  character  have  been 
changed  so  that  the  geologist  has  little  difficulty  in  recognizing  the 
marks  of  this  change  and  he  can  pronounce  at  once  on  the  general 
question  of  whether  or  not  the  rocks  are  liable  to  contain  oil.  Thus 
the  crystalline  schist  and  slate  underlying  the  Newark  rocks  bear  all 
the  ear-marks  of  having  been  greatly  metamorphosed  and  no  geologist 
would  consider  for  a moment  the  possibility  of  their  containing  oil, 
except  possibly  very  locally,  where  oil  may  have  recently  migrated  into 
them  from  some  adjacent  oil-sand.  The  Newark  rocks,  on  the  other 
hand,  on  casual  inspection,  show  no  signs  of  having  been  affected  by 
heat  or  pressure,  but  such  a test  is  not  always  satisfactory,  because  in 
the  incipient  stages  of  change  there  is  little  outward  effect  apparent. 
The  most  satisfactory  indication  of  metamorphism  is  the  condition  of 
the  coal  as  shown  by  a chemical  analysis  (pp.  82  and  83).  The  com- 
parison of  many  coal  analyses  in  the  Appalachian  region  shows  that 
the  great  oil  pools  are  found  where  the  fixed  carbon  in  the  coal  in  the 
C form  (see  table  of  analyses)  is  less  than  60  and  that  little  if  ar.y 
oil  is  found  where  the  fixed  carbon  is  more  than  65  per  cent.  The 
fixed  carbon  in  the  Deep  River  coals  ranges  in  the  C form  from  62.4  to 
64.9,  hence  the  rocks  are  metamorphosed  to  such  an  extent  that  it  is 
doubtful  if  any  oil  remains,  granting  that  it  formerly  existed  in  the 
rocks.  It  seems  certain  that  no  oil  pool  of  consequence  would  ever  be 
found  in  these  rocks,  but  the  chance  for  finding  natural  gas  is  much 
better  than  that  for  finding  oil. 

The  relation  of  the  dikes  to  the  possible  occurrence  of  oil  has  already 
been  mentioned  (p.  48),  but  it  is  worth  repeating  here  for  the  benefit  of 
those  who  may  be  tempted  to  drill  test  wells  in  this  field.  The  dikes 
act  as  barriers  to  the  circulation  of  water  and  the  inhabitants  have 
long  ago  learned  that  the  most  favorable  place  to  find  a supply  of 
water  is  near  a dike.  If  the  dike  serves  as  a barrier  to  the  circulation 
of  water,  it  doubtless  would  serve  the  same  purpose  to  the  circulation  of 
oil,  and  hence,  if  there  is  any  oil  in  the  rocks,  it  would  be  liable  to 
accumulate  near  the  dike  and  a well  located  in  such  a position  as  to 
penetrate  the  oil  sand  near  a dike  would  be  much  more  likely  to  be 
successful  than  would  one  located  at  a distance  from  a dike.  As  many 
of  the  dikes  are  doubtless  inclined  one  way  or  the  other,  it  would  be 
impossible  to  determine  the  exact  distance  from  the  dike  on  the  surface 
at  which  a well  should  he  located  so  as  to  penetrate  a given  sand  close 
to  the  dike,  but  an  attempt  should  be  made  to  secure  this  sort  of  a 
location. 


THE  DEEP  KIVER  COAL  FIELD 


95 


Conclusions. — From  a geological  point  of  view,  the  writers  have  no 
hesitation  in  saying  that  all  of  the  evidence  they  were  able  to  collect 
in  the  field,  bearing  on  this  question,  is  of  a negative  character.  The 
thinness  of  strata  bearing  organic  material  and  its  apparent  restriction 
to  the  northwestern  margin  of  the  troughs  makes  it  impossible  to 
conceive  of  it  as  a possible  source  of  a commercial  quantity  of  oil. 
But  even  if  we  grant  that  at  some  time  in  the  past,  oil  may  have  been 
distilled  from  the  organic  material  entombed  in  the  rocks,  there  are 
few,  if  any,  anticlines  in  which  it  may  have  accumulated,  and  without 
such  structures  the  volatile  constituents  of  the  oil  have  had  ample 
opportunity  to  escape  through  the  coarse  conglomerate  which  composes 
most  of  the  ISTewark  group. 

As,  however,  many  of  the  citizens  of  this  field  would  like  to  see  a 
deep  well  drilled  so  as  to  settle  the  question  regarding  the  presence 
or  absence  of  petroleum,  the  writers  were  on  the  lookout  throughout  the 
time  spent  in  the  field  for  a location  that  might  be  considered  the  best, 
from  a geological  point  of  view,  to  drill  a test  well,  but  after  mature 
consideration  of  all  of  the  facts  that  were  obtained  they  regard  all 
locations  as  unfavorable  and  are  unable  to  say  that  any  one  location  is 
more  favorable  than  another.  IST o one,  even  the  most  experienced 
geologist  can  say  positively  that  oil  does  not  occur  in  these  rocks,  hut 
they  can  say  that  all  of  the  facts  obtainable  are  of  a negative  character, 
and  that  in  their  opinion  it  is  not  worth  spending  time  or  money  in 
prospecting  where  conditions  appear  to  be  so  unfavorable. 

Sometimes  the  drilling  of  a test  well  will  satisfy  public  opinion 
regarding  the  presence  or  absence  of  petroleum  much  better  than  the 
opinion  of  the  most  eminent  geologist,  but  in  such  a case  as  the  Deep 
River  Coal  Field,  where  there  is  no  pronounced  anticline,  one  well  would 
test  only  the  possibilities  in  its  immediate  vicinity,  hut  would  tell  noth- 
ing about  oil  possibilities  in  the  territory  surrounding  the  well.  Under 
such  conditions,  it  would  require  many  wells,  unless  the  driller  were 
fortunate  enough  to  strike  oil  in  his  first  or  second  venture.  Altogether 
the  adequate  testing  of  this  field  might  prove  to  be  very  expensive, 
with  no  returns,  and  in  such  an  event  it  would  have  been  much  better 
to  spend  the  money  in  building  good  roads  or  in  improving  the  soil, 
or  in  some  enterprise  that  would  redound  to  the  benefit  of  the  entire 
community,  rather  than  in  a hole  in  the  ground  that  yielded  nothing. 


OctiS’fTft 

lar:-'38V 


Date  Due 


JAN  I 3 *47 

lJUV  2 

IP  2 $ ? ' 

Form  335— 40M— 6-39— S 

* "557.56  N873B  82069 

N«C.  -fteolosioal  and -.Econo- 
mic -Survey — 

Bulletin  No.  32 


557.56  N873B  no. 33  82069 


